diff --git a/go_backend/audio_metadata_supplement_test.go b/go_backend/audio_metadata_supplement_test.go
index 6dbf999e..4348344e 100644
--- a/go_backend/audio_metadata_supplement_test.go
+++ b/go_backend/audio_metadata_supplement_test.go
@@ -308,16 +308,20 @@ func TestM4AMetadataAtomHelpers(t *testing.T) {
 		t.Fatalf("ReplayGain fields = %#v", fields)
 	}
 
-	qualityPath := filepath.Join(dir, "quality.m4a")
+	qualityPath := filepath.Join(dir, "quality-alac.m4a")
 	mvhd := make([]byte, 20)
 	binary.BigEndian.PutUint32(mvhd[12:16], 1000)
 	binary.BigEndian.PutUint32(mvhd[16:20], 180000)
 	sampleEntry := make([]byte, 32)
-	copy(sampleEntry[0:4], "mp4a")
+	copy(sampleEntry[0:4], "alac")
 	binary.BigEndian.PutUint16(sampleEntry[22:24], 24)
 	sampleEntry[28] = 0xAC
 	sampleEntry[29] = 0x44
-	qualityFile := append(buildM4AAtom("ftyp", []byte("M4A \x00\x00\x00\x00")), buildM4AAtom("moov", append(buildM4AAtom("mvhd", mvhd), sampleEntry...))...)
+	alacConfig := make([]byte, 24)
+	alacConfig[5] = 24
+	binary.BigEndian.PutUint32(alacConfig[20:24], 44100)
+	alacEntryPayload := append(append([]byte{}, sampleEntry[4:]...), buildM4AAtom("alac", alacConfig)...)
+	qualityFile := append(buildM4AAtom("ftyp", []byte("M4A \x00\x00\x00\x00")), buildM4AAtom("moov", append(buildM4AAtom("mvhd", mvhd), buildM4AAtom("alac", alacEntryPayload)...))...)
 	if err := os.WriteFile(qualityPath, qualityFile, 0600); err != nil {
 		t.Fatal(err)
 	}
@@ -327,6 +331,15 @@ func TestM4AMetadataAtomHelpers(t *testing.T) {
 	if quality, err := GetAudioQuality(qualityPath); err != nil || quality.SampleRate != 44100 {
 		t.Fatalf("GetAudioQuality M4A = %#v/%v", quality, err)
 	}
+	aacQualityPath := filepath.Join(dir, "quality-aac.m4a")
+	copy(sampleEntry[0:4], "mp4a")
+	aacQualityFile := append(buildM4AAtom("ftyp", []byte("M4A \x00\x00\x00\x00")), buildM4AAtom("moov", append(buildM4AAtom("mvhd", mvhd), sampleEntry...))...)
+	if err := os.WriteFile(aacQualityPath, aacQualityFile, 0600); err != nil {
+		t.Fatal(err)
+	}
+	if quality, err := GetM4AQuality(aacQualityPath); err != nil || quality.BitDepth != 0 || quality.SampleRate != 44100 || quality.Duration != 180 {
+		t.Fatalf("GetM4AQuality AAC = %#v/%v", quality, err)
+	}
 	if _, _, ok := parseALACSpecificConfig(make([]byte, 4)); ok {
 		t.Fatal("short ALAC config should not parse")
 	}
diff --git a/go_backend/metadata.go b/go_backend/metadata.go
index cfa8432e..3db29102 100644
--- a/go_backend/metadata.go
+++ b/go_backend/metadata.go
@@ -1695,9 +1695,10 @@ func GetM4AQuality(filePath string) (AudioQuality, error) {
 	//   [26:28] reserved
 	//   [28:32] samplerate (16.16 fixed-point)
 	sampleRate := int(buf[28])<<8 | int(buf[29])
-	bitDepth := int(buf[22])<<8 | int(buf[23])
+	bitDepth := 0
 
 	if atomType == "alac" {
+		bitDepth = int(buf[22])<<8 | int(buf[23])
 		if alacBitDepth, alacSampleRate, ok := readALACSpecificConfig(f, sampleOffset, fileSize); ok {
 			if alacBitDepth > 0 {
 				bitDepth = alacBitDepth
@@ -1708,10 +1709,6 @@ func GetM4AQuality(filePath string) (AudioQuality, error) {
 		}
 	}
 
-	if bitDepth <= 0 {
-		bitDepth = 16
-	}
-
 	return AudioQuality{BitDepth: bitDepth, SampleRate: sampleRate, Duration: duration}, nil
 }