diff --git a/.golangci.yml b/.golangci.yml
index 33a993a4..1ac50f4c 100644
--- a/.golangci.yml
+++ b/.golangci.yml
@@ -68,4 +68,3 @@ linters-settings:
     disable:
     - fieldalignment
     - reflectvaluecompare
-    - shadow
diff --git a/internal/auth/manager.go b/internal/auth/manager.go
index c58dcebb..f43f5188 100644
--- a/internal/auth/manager.go
+++ b/internal/auth/manager.go
@@ -275,13 +275,13 @@ func (m *Manager) authenticateJWT(req *Request) error {
 		return fmt.Errorf("JWT not provided")
 	}
 
-	var customClaims customClaims
-	_, err = jwt.ParseWithClaims(v["jwt"][0], &customClaims, keyfunc)
+	var cc customClaims
+	_, err = jwt.ParseWithClaims(v["jwt"][0], &cc, keyfunc)
 	if err != nil {
 		return err
 	}
 
-	if !matchesPermission(customClaims.MediaMTXPermissions, req) {
+	if !matchesPermission(cc.MediaMTXPermissions, req) {
 		return fmt.Errorf("user doesn't have permission to perform action")
 	}
 
diff --git a/internal/auth/manager_test.go b/internal/auth/manager_test.go
index 14498cb5..764605e5 100644
--- a/internal/auth/manager_test.go
+++ b/internal/auth/manager_test.go
@@ -309,8 +309,8 @@ func TestAuthJWT(t *testing.T) {
 
 	httpServ := &http.Server{
 		Handler: http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
-			response, err := jwkSet.JSONPublic(r.Context())
-			if err != nil {
+			response, err2 := jwkSet.JSONPublic(r.Context())
+			if err2 != nil {
 				w.WriteHeader(http.StatusInternalServerError)
 				return
 			}
diff --git a/internal/core/api_test.go b/internal/core/api_test.go
index 829f956d..33cf0a3d 100644
--- a/internal/core/api_test.go
+++ b/internal/core/api_test.go
@@ -506,7 +506,7 @@ func TestAPIProtocolListGet(t *testing.T) {
 				go func() {
 					time.Sleep(500 * time.Millisecond)
 
-					err := source.WritePacketRTP(medi, &rtp.Packet{
+					err2 := source.WritePacketRTP(medi, &rtp.Packet{
 						Header: rtp.Header{
 							Version:        2,
 							Marker:         true,
@@ -517,7 +517,7 @@ func TestAPIProtocolListGet(t *testing.T) {
 						},
 						Payload: []byte{5, 1, 2, 3, 4},
 					})
-					require.NoError(t, err)
+					require.NoError(t, err2)
 				}()
 
 				c := &webrtc.WHIPClient{
diff --git a/internal/core/core.go b/internal/core/core.go
index a749cf19..f7476f84 100644
--- a/internal/core/core.go
+++ b/internal/core/core.go
@@ -305,7 +305,7 @@ func (p *Core) createResources(initial bool) error {
 			AuthManager:    p.authManager,
 			Parent:         p,
 		}
-		err := i.Initialize()
+		err = i.Initialize()
 		if err != nil {
 			return err
 		}
@@ -325,7 +325,7 @@ func (p *Core) createResources(initial bool) error {
 			AuthManager:    p.authManager,
 			Parent:         p,
 		}
-		err := i.Initialize()
+		err = i.Initialize()
 		if err != nil {
 			return err
 		}
@@ -356,7 +356,7 @@ func (p *Core) createResources(initial bool) error {
 			AuthManager:    p.authManager,
 			Parent:         p,
 		}
-		err := i.Initialize()
+		err = i.Initialize()
 		if err != nil {
 			return err
 		}
@@ -415,7 +415,7 @@ func (p *Core) createResources(initial bool) error {
 			PathManager:         p.pathManager,
 			Parent:              p,
 		}
-		err := i.Initialize()
+		err = i.Initialize()
 		if err != nil {
 			return err
 		}
@@ -455,7 +455,7 @@ func (p *Core) createResources(initial bool) error {
 			PathManager:         p.pathManager,
 			Parent:              p,
 		}
-		err := i.Initialize()
+		err = i.Initialize()
 		if err != nil {
 			return err
 		}
@@ -486,7 +486,7 @@ func (p *Core) createResources(initial bool) error {
 			PathManager:         p.pathManager,
 			Parent:              p,
 		}
-		err := i.Initialize()
+		err = i.Initialize()
 		if err != nil {
 			return err
 		}
@@ -517,7 +517,7 @@ func (p *Core) createResources(initial bool) error {
 			PathManager:         p.pathManager,
 			Parent:              p,
 		}
-		err := i.Initialize()
+		err = i.Initialize()
 		if err != nil {
 			return err
 		}
@@ -549,7 +549,7 @@ func (p *Core) createResources(initial bool) error {
 			PathManager:     p.pathManager,
 			Parent:          p,
 		}
-		err := i.Initialize()
+		err = i.Initialize()
 		if err != nil {
 			return err
 		}
@@ -583,7 +583,7 @@ func (p *Core) createResources(initial bool) error {
 			PathManager:           p.pathManager,
 			Parent:                p,
 		}
-		err := i.Initialize()
+		err = i.Initialize()
 		if err != nil {
 			return err
 		}
@@ -610,7 +610,7 @@ func (p *Core) createResources(initial bool) error {
 			PathManager:         p.pathManager,
 			Parent:              p,
 		}
-		err := i.Initialize()
+		err = i.Initialize()
 		if err != nil {
 			return err
 		}
@@ -643,7 +643,7 @@ func (p *Core) createResources(initial bool) error {
 			SRTServer:      p.srtServer,
 			Parent:         p,
 		}
-		err := i.Initialize()
+		err = i.Initialize()
 		if err != nil {
 			return err
 		}
diff --git a/internal/core/metrics_test.go b/internal/core/metrics_test.go
index 5cb09c94..5237e57c 100644
--- a/internal/core/metrics_test.go
+++ b/internal/core/metrics_test.go
@@ -169,10 +169,10 @@ webrtc_sessions_bytes_sent 0
 
 			tr := &http.Transport{}
 			defer tr.CloseIdleConnections()
-			hc := &http.Client{Transport: tr}
+			hc2 := &http.Client{Transport: tr}
 
 			s := &webrtc.WHIPClient{
-				HTTPClient: hc,
+				HTTPClient: hc2,
 				URL:        su,
 				Log:        test.NilLogger,
 			}
diff --git a/internal/core/path_test.go b/internal/core/path_test.go
index 0b21759c..90e31900 100644
--- a/internal/core/path_test.go
+++ b/internal/core/path_test.go
@@ -425,7 +425,7 @@ func TestPathRunOnRead(t *testing.T) {
 							case <-writerTerminate:
 								return
 							}
-							err := source.WritePacketRTP(media0, &rtp.Packet{
+							err2 := source.WritePacketRTP(media0, &rtp.Packet{
 								Header: rtp.Header{
 									Version:        2,
 									Marker:         true,
@@ -436,7 +436,7 @@ func TestPathRunOnRead(t *testing.T) {
 								},
 								Payload: []byte{5},
 							})
-							require.NoError(t, err)
+							require.NoError(t, err2)
 							i++
 						}
 					}()
@@ -525,7 +525,7 @@ func TestPathRecord(t *testing.T) {
 	defer source.Close()
 
 	for i := 0; i < 4; i++ {
-		err := source.WritePacketRTP(media0, &rtp.Packet{
+		err = source.WritePacketRTP(media0, &rtp.Packet{
 			Header: rtp.Header{
 				Version:        2,
 				Marker:         true,
@@ -562,7 +562,7 @@ func TestPathRecord(t *testing.T) {
 	time.Sleep(500 * time.Millisecond)
 
 	for i := 4; i < 8; i++ {
-		err := source.WritePacketRTP(media0, &rtp.Packet{
+		err = source.WritePacketRTP(media0, &rtp.Packet{
 			Header: rtp.Header{
 				Version:        2,
 				Marker:         true,
@@ -761,7 +761,7 @@ func TestPathOverridePublisher(t *testing.T) {
 			require.NoError(t, err)
 
 			if ca == "enabled" {
-				err := s1.Wait()
+				err = s1.Wait()
 				require.EqualError(t, err, "EOF")
 
 				err = s2.WritePacketRTP(medi, &rtp.Packet{
diff --git a/internal/formatprocessor/h264.go b/internal/formatprocessor/h264.go
index 7f0f11af..0d5cf289 100644
--- a/internal/formatprocessor/h264.go
+++ b/internal/formatprocessor/h264.go
@@ -30,7 +30,7 @@ func rtpH264ExtractParams(payload []byte) ([]byte, []byte) {
 		return nil, payload
 
 	case h264.NALUTypeSTAPA:
-		payload := payload[1:]
+		payload = payload[1:]
 		var sps []byte
 		var pps []byte
 
diff --git a/internal/formatprocessor/h265.go b/internal/formatprocessor/h265.go
index e04cafe4..eaa336d1 100644
--- a/internal/formatprocessor/h265.go
+++ b/internal/formatprocessor/h265.go
@@ -33,7 +33,7 @@ func rtpH265ExtractParams(payload []byte) ([]byte, []byte, []byte) {
 		return nil, nil, payload
 
 	case h265.NALUType_AggregationUnit:
-		payload := payload[2:]
+		payload = payload[2:]
 		var vps []byte
 		var sps []byte
 		var pps []byte
diff --git a/internal/playback/mp4/presentation.go b/internal/playback/mp4/presentation.go
index fa01b6b3..0f12bfe5 100644
--- a/internal/playback/mp4/presentation.go
+++ b/internal/playback/mp4/presentation.go
@@ -134,7 +134,8 @@ func (p *Presentation) marshalFtypAndMoov(w io.Writer) error {
 	stcosOffsets := make([]int, len(p.Tracks))
 
 	for i, track := range p.Tracks {
-		res, err := track.marshal(mw)
+		var res *headerTrackMarshalResult
+		res, err = track.marshal(mw)
 		if err != nil {
 			return err
 		}
diff --git a/internal/playback/mp4/track.go b/internal/playback/mp4/track.go
index 07dff1f8..d21743e4 100644
--- a/internal/playback/mp4/track.go
+++ b/internal/playback/mp4/track.go
@@ -354,7 +354,8 @@ func (t *Track) marshal(w *mp4Writer) (*headerTrackMarshalResult, error) {
 			return nil, err
 		}
 
-		bs, err := av1.BitstreamMarshal([][]byte{codec.SequenceHeader})
+		var bs []byte
+		bs, err = av1.BitstreamMarshal([][]byte{codec.SequenceHeader})
 		if err != nil {
 			return nil, err
 		}
diff --git a/internal/playback/on_get.go b/internal/playback/on_get.go
index dca27721..7b793227 100644
--- a/internal/playback/on_get.go
+++ b/internal/playback/on_get.go
@@ -73,13 +73,14 @@ func seekAndMux(
 		segmentEnd = start.Add(segmentMaxElapsed)
 
 		for _, seg := range segments[1:] {
-			f, err := os.Open(seg.Fpath)
+			f, err = os.Open(seg.Fpath)
 			if err != nil {
 				return err
 			}
 			defer f.Close()
 
-			init, err := segmentFMP4ReadInit(f)
+			var init *fmp4.Init
+			init, err = segmentFMP4ReadInit(f)
 			if err != nil {
 				return err
 			}
@@ -90,7 +91,8 @@ func seekAndMux(
 
 			segmentStartOffset := seg.Start.Sub(start)
 
-			segmentMaxElapsed, err := segmentFMP4MuxParts(f, segmentStartOffset, duration, firstInit, m)
+			var segmentMaxElapsed time.Duration
+			segmentMaxElapsed, err = segmentFMP4MuxParts(f, segmentStartOffset, duration, firstInit, m)
 			if err != nil {
 				return err
 			}
diff --git a/internal/playback/segment_fmp4.go b/internal/playback/segment_fmp4.go
index 6a612ab8..e1619f8f 100644
--- a/internal/playback/segment_fmp4.go
+++ b/internal/playback/segment_fmp4.go
@@ -159,7 +159,8 @@ func segmentFMP4ReadMaxDuration(
 	lastMoofPos := int64(-1)
 
 	for {
-		moofPos, err := r.Seek(0, io.SeekCurrent)
+		var moofPos int64
+		moofPos, err = r.Seek(0, io.SeekCurrent)
 		if err != nil {
 			return 0, err
 		}
@@ -423,9 +424,9 @@ func segmentFMP4SeekAndMuxParts(
 					e.SampleSize,
 					func() ([]byte, error) {
 						payload := make([]byte, sampleSize)
-						n, err := r.ReadAt(payload, int64(sampleOffset))
-						if err != nil {
-							return nil, err
+						n, err2 := r.ReadAt(payload, int64(sampleOffset))
+						if err2 != nil {
+							return nil, err2
 						}
 						if n != int(sampleSize) {
 							return nil, fmt.Errorf("partial read")
@@ -547,9 +548,9 @@ func segmentFMP4MuxParts(
 					e.SampleSize,
 					func() ([]byte, error) {
 						payload := make([]byte, sampleSize)
-						n, err := r.ReadAt(payload, int64(sampleOffset))
-						if err != nil {
-							return nil, err
+						n, err2 := r.ReadAt(payload, int64(sampleOffset))
+						if err2 != nil {
+							return nil, err2
 						}
 						if n != int(sampleSize) {
 							return nil, fmt.Errorf("partial read")
diff --git a/internal/playback/segment_fmp4_test.go b/internal/playback/segment_fmp4_test.go
index e93d5f67..178af562 100644
--- a/internal/playback/segment_fmp4_test.go
+++ b/internal/playback/segment_fmp4_test.go
@@ -60,7 +60,7 @@ func BenchmarkFMP4ReadInit(b *testing.B) {
 
 	for n := 0; n < b.N; n++ {
 		func() {
-			f, err := os.Open(f.Name())
+			f, err = os.Open(f.Name())
 			if err != nil {
 				panic(err)
 			}
diff --git a/internal/protocols/rtmp/chunk/chunk0.go b/internal/protocols/rtmp/chunk/chunk0.go
index f0e0323d..e9eea678 100644
--- a/internal/protocols/rtmp/chunk/chunk0.go
+++ b/internal/protocols/rtmp/chunk/chunk0.go
@@ -32,7 +32,7 @@ func (c *Chunk0) Read(r io.Reader, maxBodyLen uint32, _ bool) error {
 	c.MessageStreamID = uint32(header[8])<<24 | uint32(header[9])<<16 | uint32(header[10])<<8 | uint32(header[11])
 
 	if c.Timestamp >= 0xFFFFFF {
-		_, err := io.ReadFull(r, header[:4])
+		_, err = io.ReadFull(r, header[:4])
 		if err != nil {
 			return err
 		}
diff --git a/internal/protocols/rtmp/chunk/chunk3.go b/internal/protocols/rtmp/chunk/chunk3.go
index ea953b53..38f3269f 100644
--- a/internal/protocols/rtmp/chunk/chunk3.go
+++ b/internal/protocols/rtmp/chunk/chunk3.go
@@ -26,7 +26,7 @@ func (c *Chunk3) Read(r io.Reader, bodyLen uint32, hasExtendedTimestamp bool) er
 	c.ChunkStreamID = header[0] & 0x3F
 
 	if hasExtendedTimestamp {
-		_, err := io.ReadFull(r, header[:4])
+		_, err = io.ReadFull(r, header[:4])
 		if err != nil {
 			return err
 		}
diff --git a/internal/protocols/rtmp/conn.go b/internal/protocols/rtmp/conn.go
index c9c25f65..8a0222c3 100644
--- a/internal/protocols/rtmp/conn.go
+++ b/internal/protocols/rtmp/conn.go
@@ -342,7 +342,6 @@ func (c *Conn) initializeServer() (*url.URL, bool, error) {
 
 	var rw io.ReadWriter
 	if keyIn != nil {
-		var err error
 		rw, err = newRC4ReadWriter(c.bc, keyIn, keyOut)
 		if err != nil {
 			return nil, false, err
diff --git a/internal/protocols/rtmp/conn_test.go b/internal/protocols/rtmp/conn_test.go
index 28ab6d47..3b632c82 100644
--- a/internal/protocols/rtmp/conn_test.go
+++ b/internal/protocols/rtmp/conn_test.go
@@ -28,37 +28,37 @@ func TestNewClientConn(t *testing.T) {
 			done := make(chan struct{})
 
 			go func() {
-				conn, err := ln.Accept()
-				require.NoError(t, err)
+				conn, err2 := ln.Accept()
+				require.NoError(t, err2)
 				defer conn.Close()
 				bc := bytecounter.NewReadWriter(conn)
 
-				_, _, err = handshake.DoServer(bc, false)
-				require.NoError(t, err)
+				_, _, err2 = handshake.DoServer(bc, false)
+				require.NoError(t, err2)
 
 				mrw := message.NewReadWriter(bc, bc, true)
 
-				msg, err := mrw.Read()
-				require.NoError(t, err)
+				msg, err2 := mrw.Read()
+				require.NoError(t, err2)
 				require.Equal(t, &message.SetWindowAckSize{
 					Value: 2500000,
 				}, msg)
 
-				msg, err = mrw.Read()
-				require.NoError(t, err)
+				msg, err2 = mrw.Read()
+				require.NoError(t, err2)
 				require.Equal(t, &message.SetPeerBandwidth{
 					Value: 2500000,
 					Type:  2,
 				}, msg)
 
-				msg, err = mrw.Read()
-				require.NoError(t, err)
+				msg, err2 = mrw.Read()
+				require.NoError(t, err2)
 				require.Equal(t, &message.SetChunkSize{
 					Value: 65536,
 				}, msg)
 
-				msg, err = mrw.Read()
-				require.NoError(t, err)
+				msg, err2 = mrw.Read()
+				require.NoError(t, err2)
 				require.Equal(t, &message.CommandAMF0{
 					ChunkStreamID: 3,
 					Name:          "connect",
@@ -77,7 +77,7 @@ func TestNewClientConn(t *testing.T) {
 					},
 				}, msg)
 
-				err = mrw.Write(&message.CommandAMF0{
+				err2 = mrw.Write(&message.CommandAMF0{
 					ChunkStreamID: 3,
 					Name:          "_result",
 					CommandID:     1,
@@ -94,12 +94,12 @@ func TestNewClientConn(t *testing.T) {
 						},
 					},
 				})
-				require.NoError(t, err)
+				require.NoError(t, err2)
 
 				switch ca {
 				case "read", "read nginx rtmp":
-					msg, err = mrw.Read()
-					require.NoError(t, err)
+					msg, err2 = mrw.Read()
+					require.NoError(t, err2)
 					require.Equal(t, &message.CommandAMF0{
 						ChunkStreamID: 3,
 						Name:          "createStream",
@@ -109,7 +109,7 @@ func TestNewClientConn(t *testing.T) {
 						},
 					}, msg)
 
-					err = mrw.Write(&message.CommandAMF0{
+					err2 = mrw.Write(&message.CommandAMF0{
 						ChunkStreamID: 3,
 						Name:          "_result",
 						CommandID:     2,
@@ -118,16 +118,16 @@ func TestNewClientConn(t *testing.T) {
 							float64(1),
 						},
 					})
-					require.NoError(t, err)
+					require.NoError(t, err2)
 
-					msg, err = mrw.Read()
-					require.NoError(t, err)
+					msg, err2 = mrw.Read()
+					require.NoError(t, err2)
 					require.Equal(t, &message.UserControlSetBufferLength{
 						BufferLength: 0x64,
 					}, msg)
 
-					msg, err = mrw.Read()
-					require.NoError(t, err)
+					msg, err2 = mrw.Read()
+					require.NoError(t, err2)
 					require.Equal(t, &message.CommandAMF0{
 						ChunkStreamID:   4,
 						MessageStreamID: 0x1000000,
@@ -139,7 +139,7 @@ func TestNewClientConn(t *testing.T) {
 						},
 					}, msg)
 
-					err = mrw.Write(&message.CommandAMF0{
+					err2 = mrw.Write(&message.CommandAMF0{
 						ChunkStreamID:   5,
 						MessageStreamID: 0x1000000,
 						Name:            "onStatus",
@@ -158,11 +158,11 @@ func TestNewClientConn(t *testing.T) {
 							},
 						},
 					})
-					require.NoError(t, err)
+					require.NoError(t, err2)
 
 				case "publish":
-					msg, err = mrw.Read()
-					require.NoError(t, err)
+					msg, err2 = mrw.Read()
+					require.NoError(t, err2)
 					require.Equal(t, &message.CommandAMF0{
 						ChunkStreamID: 3,
 						Name:          "releaseStream",
@@ -173,8 +173,8 @@ func TestNewClientConn(t *testing.T) {
 						},
 					}, msg)
 
-					msg, err = mrw.Read()
-					require.NoError(t, err)
+					msg, err2 = mrw.Read()
+					require.NoError(t, err2)
 					require.Equal(t, &message.CommandAMF0{
 						ChunkStreamID: 3,
 						Name:          "FCPublish",
@@ -185,8 +185,8 @@ func TestNewClientConn(t *testing.T) {
 						},
 					}, msg)
 
-					msg, err = mrw.Read()
-					require.NoError(t, err)
+					msg, err2 = mrw.Read()
+					require.NoError(t, err2)
 					require.Equal(t, &message.CommandAMF0{
 						ChunkStreamID: 3,
 						Name:          "createStream",
@@ -196,7 +196,7 @@ func TestNewClientConn(t *testing.T) {
 						},
 					}, msg)
 
-					err = mrw.Write(&message.CommandAMF0{
+					err2 = mrw.Write(&message.CommandAMF0{
 						ChunkStreamID: 3,
 						Name:          "_result",
 						CommandID:     4,
@@ -205,10 +205,10 @@ func TestNewClientConn(t *testing.T) {
 							float64(1),
 						},
 					})
-					require.NoError(t, err)
+					require.NoError(t, err2)
 
-					msg, err = mrw.Read()
-					require.NoError(t, err)
+					msg, err2 = mrw.Read()
+					require.NoError(t, err2)
 					require.Equal(t, &message.CommandAMF0{
 						ChunkStreamID:   4,
 						MessageStreamID: 0x1000000,
@@ -221,7 +221,7 @@ func TestNewClientConn(t *testing.T) {
 						},
 					}, msg)
 
-					err = mrw.Write(&message.CommandAMF0{
+					err2 = mrw.Write(&message.CommandAMF0{
 						ChunkStreamID:   5,
 						MessageStreamID: 0x1000000,
 						Name:            "onStatus",
@@ -235,7 +235,7 @@ func TestNewClientConn(t *testing.T) {
 							},
 						},
 					})
-					require.NoError(t, err)
+					require.NoError(t, err2)
 				}
 
 				close(done)
@@ -280,12 +280,12 @@ func TestNewServerConn(t *testing.T) {
 			done := make(chan struct{})
 
 			go func() {
-				nconn, err := ln.Accept()
-				require.NoError(t, err)
+				nconn, err2 := ln.Accept()
+				require.NoError(t, err2)
 				defer nconn.Close()
 
-				_, u, isPublishing, err := NewServerConn(nconn)
-				require.NoError(t, err)
+				_, u, isPublishing, err2 := NewServerConn(nconn)
+				require.NoError(t, err2)
 
 				require.Equal(t, &url.URL{
 					Scheme: "rtmp",
diff --git a/internal/protocols/rtmp/reader.go b/internal/protocols/rtmp/reader.go
index 99bc79ba..e881b6e2 100644
--- a/internal/protocols/rtmp/reader.go
+++ b/internal/protocols/rtmp/reader.go
@@ -47,8 +47,8 @@ func hasVideo(md amf0.Object) (bool, error) {
 	v, ok := md.Get("videocodecid")
 	if !ok {
 		// some Dahua cameras send width and height without videocodecid
-		if v, ok := md.Get("width"); ok {
-			if vf, ok := v.(float64); ok && vf != 0 {
+		if v2, ok := md.Get("width"); ok {
+			if vf, ok := v2.(float64); ok && vf != 0 {
 				return true, nil
 			}
 		}
@@ -219,7 +219,8 @@ func tracksFromMetadata(conn *Conn, payload []interface{}) (format.Format, forma
 
 					// format used by OBS < 29.1 to publish H265
 				} else if msg.Type == message.VideoTypeAU && msg.IsKeyFrame {
-					nalus, err := h264.AVCCUnmarshal(msg.Payload)
+					var nalus [][]byte
+					nalus, err = h264.AVCCUnmarshal(msg.Payload)
 					if err != nil {
 						if errors.Is(err, h264.ErrAVCCNoNALUs) {
 							continue
@@ -271,7 +272,7 @@ func tracksFromMetadata(conn *Conn, payload []interface{}) (format.Format, forma
 				switch msg.FourCC {
 				case message.FourCCHEVC:
 					var hvcc mp4.HvcC
-					_, err := mp4.Unmarshal(bytes.NewReader(msg.Config), uint64(len(msg.Config)), &hvcc, mp4.Context{})
+					_, err = mp4.Unmarshal(bytes.NewReader(msg.Config), uint64(len(msg.Config)), &hvcc, mp4.Context{})
 					if err != nil {
 						return nil, nil, fmt.Errorf("invalid H265 configuration: %w", err)
 					}
@@ -292,7 +293,7 @@ func tracksFromMetadata(conn *Conn, payload []interface{}) (format.Format, forma
 
 				case message.FourCCAV1:
 					var av1c mp4.Av1C
-					_, err := mp4.Unmarshal(bytes.NewReader(msg.Config), uint64(len(msg.Config)), &av1c, mp4.Context{})
+					_, err = mp4.Unmarshal(bytes.NewReader(msg.Config), uint64(len(msg.Config)), &av1c, mp4.Context{})
 					if err != nil {
 						return nil, nil, fmt.Errorf("invalid AV1 configuration: %w", err)
 					}
@@ -309,7 +310,7 @@ func tracksFromMetadata(conn *Conn, payload []interface{}) (format.Format, forma
 
 				default: // VP9
 					var vpcc mp4.VpcC
-					_, err := mp4.Unmarshal(bytes.NewReader(msg.Config), uint64(len(msg.Config)), &vpcc, mp4.Context{})
+					_, err = mp4.Unmarshal(bytes.NewReader(msg.Config), uint64(len(msg.Config)), &vpcc, mp4.Context{})
 					if err != nil {
 						return nil, nil, fmt.Errorf("invalid VP9 configuration: %w", err)
 					}
diff --git a/internal/protocols/rtmp/reader_test.go b/internal/protocols/rtmp/reader_test.go
index 0853ea3a..052eeb19 100644
--- a/internal/protocols/rtmp/reader_test.go
+++ b/internal/protocols/rtmp/reader_test.go
@@ -147,12 +147,12 @@ func TestReadTracks(t *testing.T) {
 					IsStereo:        true,
 					AACType:         message.AudioAACTypeConfig,
 					Payload: func() []byte {
-						enc, err := mpeg4audio.Config{
+						enc, err2 := mpeg4audio.Config{
 							Type:         2,
 							SampleRate:   44100,
 							ChannelCount: 2,
 						}.Marshal()
-						require.NoError(t, err)
+						require.NoError(t, err2)
 						return enc
 					}(),
 				},
@@ -267,12 +267,12 @@ func TestReadTracks(t *testing.T) {
 					IsStereo:        true,
 					AACType:         message.AudioAACTypeConfig,
 					Payload: func() []byte {
-						enc, err := mpeg4audio.Config{
+						enc, err2 := mpeg4audio.Config{
 							Type:         2,
 							SampleRate:   44100,
 							ChannelCount: 2,
 						}.Marshal()
-						require.NoError(t, err)
+						require.NoError(t, err2)
 						return enc
 					}(),
 				},
@@ -302,12 +302,12 @@ func TestReadTracks(t *testing.T) {
 					IsStereo:        true,
 					AACType:         message.AudioAACTypeConfig,
 					Payload: func() []byte {
-						enc, err := mpeg4audio.Config{
+						enc, err2 := mpeg4audio.Config{
 							Type:         2,
 							SampleRate:   44100,
 							ChannelCount: 2,
 						}.Marshal()
-						require.NoError(t, err)
+						require.NoError(t, err2)
 						return enc
 					}(),
 				},
@@ -320,12 +320,12 @@ func TestReadTracks(t *testing.T) {
 					IsStereo:        true,
 					AACType:         message.AudioAACTypeConfig,
 					Payload: func() []byte {
-						enc, err := mpeg4audio.Config{
+						enc, err2 := mpeg4audio.Config{
 							Type:         2,
 							SampleRate:   44100,
 							ChannelCount: 2,
 						}.Marshal()
-						require.NoError(t, err)
+						require.NoError(t, err2)
 						return enc
 					}(),
 					DTS: 1 * time.Second,
@@ -385,12 +385,12 @@ func TestReadTracks(t *testing.T) {
 					IsKeyFrame:      true,
 					Type:            message.VideoTypeAU,
 					Payload: func() []byte {
-						avcc, err := h264.AVCCMarshal([][]byte{
+						avcc, err2 := h264.AVCCMarshal([][]byte{
 							test.FormatH265.VPS,
 							test.FormatH265.SPS,
 							test.FormatH265.PPS,
 						})
-						require.NoError(t, err)
+						require.NoError(t, err2)
 						return avcc
 					}(),
 				},
@@ -403,12 +403,12 @@ func TestReadTracks(t *testing.T) {
 					IsStereo:        true,
 					AACType:         message.AudioAACTypeConfig,
 					Payload: func() []byte {
-						enc, err := mpeg4audio.Config{
+						enc, err2 := mpeg4audio.Config{
 							Type:         2,
 							SampleRate:   44100,
 							ChannelCount: 2,
 						}.Marshal()
-						require.NoError(t, err)
+						require.NoError(t, err2)
 						return enc
 					}(),
 				},
diff --git a/internal/protocols/webrtc/whip_client.go b/internal/protocols/webrtc/whip_client.go
index 04bc5757..9c9e6a64 100644
--- a/internal/protocols/webrtc/whip_client.go
+++ b/internal/protocols/webrtc/whip_client.go
@@ -191,7 +191,7 @@ outer:
 	for {
 		select {
 		case ca := <-c.pc.NewLocalCandidate():
-			err := c.patchCandidate(ctx, offer, res.ETag, ca)
+			err = c.patchCandidate(ctx, offer, res.ETag, ca)
 			if err != nil {
 				c.deleteSession(context.Background()) //nolint:errcheck
 				c.pc.Close()
diff --git a/internal/record/agent_test.go b/internal/record/agent_test.go
index 29d2710e..0f2a18c6 100644
--- a/internal/record/agent_test.go
+++ b/internal/record/agent_test.go
@@ -189,13 +189,13 @@ func TestAgent(t *testing.T) {
 
 			if ca == "fmp4" {
 				func() {
-					f, err := os.Open(filepath.Join(dir, "mypath", "2008-05-20_22-15-25-000000."+ext))
-					require.NoError(t, err)
+					f, err2 := os.Open(filepath.Join(dir, "mypath", "2008-05-20_22-15-25-000000."+ext))
+					require.NoError(t, err2)
 					defer f.Close()
 
 					var init fmp4.Init
-					err = init.Unmarshal(f)
-					require.NoError(t, err)
+					err2 = init.Unmarshal(f)
+					require.NoError(t, err2)
 
 					require.Equal(t, fmp4.Init{
 						Tracks: []*fmp4.InitTrack{
@@ -252,7 +252,7 @@ func TestAgent(t *testing.T) {
 				_, err = os.Stat(filepath.Join(dir, "mypath", "2008-05-20_22-16-25-000000."+ext))
 				require.NoError(t, err)
 			} else {
-				_, err := os.Stat(filepath.Join(dir, "mypath", "2008-05-20_22-15-25-000000."+ext))
+				_, err = os.Stat(filepath.Join(dir, "mypath", "2008-05-20_22-15-25-000000."+ext))
 				require.NoError(t, err)
 
 				_, err = os.Stat(filepath.Join(dir, "mypath", "2008-05-20_22-16-25-000000."+ext))
diff --git a/internal/servers/rtsp/session.go b/internal/servers/rtsp/session.go
index bc705ba8..69a31c3a 100644
--- a/internal/servers/rtsp/session.go
+++ b/internal/servers/rtsp/session.go
@@ -212,8 +212,8 @@ func (s *session) onSetup(c *conn, ctx *gortsplib.ServerHandlerOnSetupCtx,
 		if err != nil {
 			var terr auth.Error
 			if errors.As(err, &terr) {
-				res, err := c.handleAuthError(terr)
-				return res, nil, err
+				res, err2 := c.handleAuthError(terr)
+				return res, nil, err2
 			}
 
 			var terr2 defs.PathNoOnePublishingError
diff --git a/internal/servers/srt/streamid_test.go b/internal/servers/srt/streamid_test.go
index 30c3a4c6..a1757bcb 100644
--- a/internal/servers/srt/streamid_test.go
+++ b/internal/servers/srt/streamid_test.go
@@ -52,10 +52,10 @@ func TestStreamIDUnmarshal(t *testing.T) {
 		},
 	} {
 		t.Run(ca.name, func(t *testing.T) {
-			var streamID streamID
-			err := streamID.unmarshal(ca.raw)
+			var sid streamID
+			err := sid.unmarshal(ca.raw)
 			require.NoError(t, err)
-			require.Equal(t, ca.dec, streamID)
+			require.Equal(t, ca.dec, sid)
 		})
 	}
 }
diff --git a/internal/staticsources/rtsp/source_test.go b/internal/staticsources/rtsp/source_test.go
index 6741d0fd..51e863c2 100644
--- a/internal/staticsources/rtsp/source_test.go
+++ b/internal/staticsources/rtsp/source_test.go
@@ -55,8 +55,8 @@ func TestSource(t *testing.T) {
 				Handler: &testServer{
 					onDescribe: func(ctx *gortsplib.ServerHandlerOnDescribeCtx,
 					) (*base.Response, *gortsplib.ServerStream, error) {
-						err := auth.Validate(ctx.Request, "testuser", "testpass", nil, nil, "IPCAM", nonce)
-						if err != nil {
+						err2 := auth.Validate(ctx.Request, "testuser", "testpass", nil, nil, "IPCAM", nonce)
+						if err2 != nil {
 							return &base.Response{ //nolint:nilerr
 								StatusCode: base.StatusUnauthorized,
 								Header: base.Header{
@@ -77,7 +77,7 @@ func TestSource(t *testing.T) {
 					onPlay: func(_ *gortsplib.ServerHandlerOnPlayCtx) (*base.Response, error) {
 						go func() {
 							time.Sleep(100 * time.Millisecond)
-							err := stream.WritePacketRTP(media0, &rtp.Packet{
+							err2 := stream.WritePacketRTP(media0, &rtp.Packet{
 								Header: rtp.Header{
 									Version:        0x02,
 									PayloadType:    96,
@@ -88,7 +88,7 @@ func TestSource(t *testing.T) {
 								},
 								Payload: []byte{5, 1, 2, 3, 4},
 							})
-							require.NoError(t, err)
+							require.NoError(t, err2)
 						}()
 
 						return &base.Response{
@@ -105,15 +105,18 @@ func TestSource(t *testing.T) {
 				s.UDPRTCPAddress = "127.0.0.1:8003"
 
 			case "tls":
-				serverCertFpath, err := test.CreateTempFile(test.TLSCertPub)
+				var serverCertFpath string
+				serverCertFpath, err = test.CreateTempFile(test.TLSCertPub)
 				require.NoError(t, err)
 				defer os.Remove(serverCertFpath)
 
-				serverKeyFpath, err := test.CreateTempFile(test.TLSCertKey)
+				var serverKeyFpath string
+				serverKeyFpath, err = test.CreateTempFile(test.TLSCertKey)
 				require.NoError(t, err)
 				defer os.Remove(serverKeyFpath)
 
-				cert, err := tls.LoadX509KeyPair(serverCertFpath, serverKeyFpath)
+				var cert tls.Certificate
+				cert, err = tls.LoadX509KeyPair(serverCertFpath, serverKeyFpath)
 				require.NoError(t, err)
 
 				s.TLSConfig = &tls.Config{Certificates: []tls.Certificate{cert}}
@@ -181,8 +184,8 @@ func TestRTSPSourceNoPassword(t *testing.T) {
 	s := gortsplib.Server{
 		Handler: &testServer{
 			onDescribe: func(ctx *gortsplib.ServerHandlerOnDescribeCtx) (*base.Response, *gortsplib.ServerStream, error) {
-				err := auth.Validate(ctx.Request, "testuser", "", nil, nil, "IPCAM", nonce)
-				if err != nil {
+				err2 := auth.Validate(ctx.Request, "testuser", "", nil, nil, "IPCAM", nonce)
+				if err2 != nil {
 					return &base.Response{ //nolint:nilerr
 						StatusCode: base.StatusUnauthorized,
 						Header: base.Header{
@@ -198,7 +201,7 @@ func TestRTSPSourceNoPassword(t *testing.T) {
 			onSetup: func(_ *gortsplib.ServerHandlerOnSetupCtx) (*base.Response, *gortsplib.ServerStream, error) {
 				go func() {
 					time.Sleep(100 * time.Millisecond)
-					err := stream.WritePacketRTP(media0, &rtp.Packet{
+					err2 := stream.WritePacketRTP(media0, &rtp.Packet{
 						Header: rtp.Header{
 							Version:        0x02,
 							PayloadType:    96,
@@ -209,7 +212,7 @@ func TestRTSPSourceNoPassword(t *testing.T) {
 						},
 						Payload: []byte{5, 1, 2, 3, 4},
 					})
-					require.NoError(t, err)
+					require.NoError(t, err2)
 				}()
 
 				return &base.Response{
diff --git a/internal/staticsources/udp/source.go b/internal/staticsources/udp/source.go
index 0c449f6c..1202b2f1 100644
--- a/internal/staticsources/udp/source.go
+++ b/internal/staticsources/udp/source.go
@@ -74,7 +74,8 @@ func (s *Source) Run(params defs.StaticSourceRunParams) error {
 			return err
 		}
 	} else {
-		tmp, err := net.ListenPacket(restrictnetwork.Restrict("udp", addr.String()))
+		var tmp net.PacketConn
+		tmp, err = net.ListenPacket(restrictnetwork.Restrict("udp", addr.String()))
 		if err != nil {
 			return err
 		}
diff --git a/internal/staticsources/webrtc/source_test.go b/internal/staticsources/webrtc/source_test.go
index e8bf85ac..7e061707 100644
--- a/internal/staticsources/webrtc/source_test.go
+++ b/internal/staticsources/webrtc/source_test.go
@@ -69,12 +69,12 @@ func TestSource(t *testing.T) {
 				require.Equal(t, "/my/resource", r.URL.Path)
 				require.Equal(t, "application/sdp", r.Header.Get("Content-Type"))
 
-				body, err := io.ReadAll(r.Body)
-				require.NoError(t, err)
+				body, err2 := io.ReadAll(r.Body)
+				require.NoError(t, err2)
 				offer := whipOffer(body)
 
-				answer, err := pc.CreateFullAnswer(context.Background(), offer)
-				require.NoError(t, err)
+				answer, err2 := pc.CreateFullAnswer(context.Background(), offer)
+				require.NoError(t, err2)
 
 				w.Header().Set("Content-Type", "application/sdp")
 				w.Header().Set("Accept-Patch", "application/trickle-ice-sdpfrag")
@@ -84,10 +84,10 @@ func TestSource(t *testing.T) {
 				w.Write([]byte(answer.SDP))
 
 				go func() {
-					err = pc.WaitUntilConnected(context.Background())
-					require.NoError(t, err)
+					err3 := pc.WaitUntilConnected(context.Background())
+					require.NoError(t, err3)
 
-					err = tracks[0].WriteRTP(&rtp.Packet{
+					err3 = tracks[0].WriteRTP(&rtp.Packet{
 						Header: rtp.Header{
 							Version:        2,
 							Marker:         true,
@@ -98,7 +98,7 @@ func TestSource(t *testing.T) {
 						},
 						Payload: []byte{5, 2},
 					})
-					require.NoError(t, err)
+					require.NoError(t, err3)
 				}()
 
 			default: