diff --git a/internal/mp4/codec_box.go b/internal/mp4/codec_box.go
index bb9630b..79c91ed 100644
--- a/internal/mp4/codec_box.go
+++ b/internal/mp4/codec_box.go
@@ -434,15 +434,15 @@ func WriteCodecBoxes(w *Writer, codec mp4.Codec, trackID int, info *CodecInfo, a
 				},
 				DataReferenceIndex: 1,
 			},
-			ChannelCount: uint16(codec.ChannelCount),
+			ChannelCount: uint16(codec.Config.ChannelCount),
 			SampleSize:   16,
-			SampleRate:   uint32(codec.SampleRate * 65536),
+			SampleRate:   uint32(codec.Config.SampleRate * 65536),
 		})
 		if err != nil {
 			return err
 		}
 
-		enc, _ := codec.Marshal()
+		enc, _ := codec.Config.Marshal()
 
 		_, err = w.WriteBox(&amp4.Esds{ // <esds/>
 			Descriptors: []amp4.Descriptor{
diff --git a/pkg/codecs/mpeg4audio/audio_specific_config.go b/pkg/codecs/mpeg4audio/audio_specific_config.go
index c9b5181..9f33f50 100644
--- a/pkg/codecs/mpeg4audio/audio_specific_config.go
+++ b/pkg/codecs/mpeg4audio/audio_specific_config.go
@@ -7,6 +7,8 @@ import (
 )
 
 // Config is an alias for AudioSpecificConfig.
+//
+// Deprecated: replaced by AudioSpecificConfig.
 type Config = AudioSpecificConfig
 
 // AudioSpecificConfig is an AudioSpecificConfig.
@@ -25,13 +27,13 @@ type AudioSpecificConfig struct {
 	CoreCoderDelay     uint16
 }
 
-// Unmarshal decodes a Config.
+// Unmarshal decodes a AudioSpecificConfig.
 func (c *AudioSpecificConfig) Unmarshal(buf []byte) error {
 	pos := 0
 	return c.UnmarshalFromPos(buf, &pos)
 }
 
-// UnmarshalFromPos decodes a Config.
+// UnmarshalFromPos decodes a AudioSpecificConfig.
 func (c *AudioSpecificConfig) UnmarshalFromPos(buf []byte, pos *int) error {
 	tmp, err := bits.ReadBits(buf, pos, 5)
 	if err != nil {
@@ -187,7 +189,7 @@ func (c AudioSpecificConfig) marshalSize() int {
 	return ret
 }
 
-// Marshal encodes a Config.
+// Marshal encodes a AudioSpecificConfig.
 func (c AudioSpecificConfig) Marshal() ([]byte, error) {
 	buf := make([]byte, c.marshalSize())
 	pos := 0
diff --git a/pkg/formats/fmp4/init.go b/pkg/formats/fmp4/init.go
index ae20a03..c578b8c 100644
--- a/pkg/formats/fmp4/init.go
+++ b/pkg/formats/fmp4/init.go
@@ -471,7 +471,7 @@ func (i *Init) Unmarshal(r io.ReadSeeker) error {
 							return nil, fmt.Errorf("unable to find decoder specific info")
 						}
 
-						var c mpeg4audio.Config
+						var c mpeg4audio.AudioSpecificConfig
 						err := c.Unmarshal(spec)
 						if err != nil {
 							return nil, fmt.Errorf("invalid MPEG-4 Audio configuration: %w", err)
diff --git a/pkg/formats/fmp4/init_test.go b/pkg/formats/fmp4/init_test.go
index ba56f53..cc895df 100644
--- a/pkg/formats/fmp4/init_test.go
+++ b/pkg/formats/fmp4/init_test.go
@@ -24,7 +24,7 @@ var testVideoTrack = &mp4.CodecH264{
 }
 
 var testAudioTrack = &mp4.CodecMPEG4Audio{
-	Config: mpeg4audio.Config{
+	Config: mpeg4audio.AudioSpecificConfig{
 		Type:         2,
 		SampleRate:   44100,
 		ChannelCount: 2,
@@ -994,7 +994,7 @@ var casesInit = []struct {
 			Tracks: []*InitTrack{
 				{
 					ID:        1,
-					TimeScale: uint32(testAudioTrack.SampleRate),
+					TimeScale: uint32(testAudioTrack.Config.SampleRate),
 					Codec:     testAudioTrack,
 				},
 			},
@@ -1461,7 +1461,7 @@ var casesInit = []struct {
 				},
 				{
 					ID:        2,
-					TimeScale: uint32(testAudioTrack.SampleRate),
+					TimeScale: uint32(testAudioTrack.Config.SampleRate),
 					Codec:     testAudioTrack,
 				},
 			},
@@ -1886,7 +1886,7 @@ func TestInitUnmarshalExternal(t *testing.T) {
 						ID:        257,
 						TimeScale: 10000000,
 						Codec: &mp4.CodecMPEG4Audio{
-							Config: mpeg4audio.Config{
+							Config: mpeg4audio.AudioSpecificConfig{
 								Type:         mpeg4audio.ObjectTypeAACLC,
 								SampleRate:   48000,
 								ChannelCount: 2,
diff --git a/pkg/formats/mp4/codec_mpeg4_audio.go b/pkg/formats/mp4/codec_mpeg4_audio.go
index 7f0fb89..803220d 100644
--- a/pkg/formats/mp4/codec_mpeg4_audio.go
+++ b/pkg/formats/mp4/codec_mpeg4_audio.go
@@ -6,7 +6,7 @@ import (
 
 // CodecMPEG4Audio is a MPEG-4 Audio codec.
 type CodecMPEG4Audio struct {
-	mpeg4audio.Config
+	Config mpeg4audio.AudioSpecificConfig
 }
 
 // IsVideo implements Codec.
diff --git a/pkg/formats/mpegts/track.go b/pkg/formats/mpegts/track.go
index fb78385..052f1ca 100644
--- a/pkg/formats/mpegts/track.go
+++ b/pkg/formats/mpegts/track.go
@@ -8,7 +8,7 @@ import (
 	"github.com/bluenviron/mediacommon/v2/pkg/codecs/mpeg4audio"
 )
 
-func findMPEG4AudioConfig(dem *astits.Demuxer, pid uint16) (*mpeg4audio.Config, error) {
+func findMPEG4AudioConfig(dem *astits.Demuxer, pid uint16) (*mpeg4audio.AudioSpecificConfig, error) {
 	for {
 		data, err := dem.NextData()
 		if err != nil {
@@ -26,7 +26,7 @@ func findMPEG4AudioConfig(dem *astits.Demuxer, pid uint16) (*mpeg4audio.Config,
 		}
 
 		pkt := adtsPkts[0]
-		return &mpeg4audio.Config{
+		return &mpeg4audio.AudioSpecificConfig{
 			Type:         pkt.Type,
 			SampleRate:   pkt.SampleRate,
 			ChannelCount: pkt.ChannelCount,
diff --git a/pkg/formats/pmp4/presentation.go b/pkg/formats/pmp4/presentation.go
index 21a1047..e1bf464 100644
--- a/pkg/formats/pmp4/presentation.go
+++ b/pkg/formats/pmp4/presentation.go
@@ -523,7 +523,7 @@ func (p *Presentation) Unmarshal(r io.ReadSeeker) error {
 						return nil, fmt.Errorf("unable to find decoder specific info")
 					}
 
-					var c mpeg4audio.Config
+					var c mpeg4audio.AudioSpecificConfig
 					err := c.Unmarshal(spec)
 					if err != nil {
 						return nil, fmt.Errorf("invalid MPEG-4 Audio configuration: %w", err)
diff --git a/pkg/formats/pmp4/presentation_test.go b/pkg/formats/pmp4/presentation_test.go
index 158475c..5063691 100644
--- a/pkg/formats/pmp4/presentation_test.go
+++ b/pkg/formats/pmp4/presentation_test.go
@@ -188,7 +188,7 @@ var casesPresentation = []struct {
 					ID:        8,
 					TimeScale: 90000,
 					Codec: &mp4.CodecMPEG4Audio{
-						Config: mpeg4audio.Config{
+						Config: mpeg4audio.AudioSpecificConfig{
 							Type:         2,
 							SampleRate:   44100,
 							ChannelCount: 2,