diff --git a/front/public/translations/en.json b/front/public/translations/en.json
index 78e33aa9..6fe0a950 100644
--- a/front/public/translations/en.json
+++ b/front/public/translations/en.json
@@ -311,6 +311,7 @@
 		"video": "Video",
 		"audio": "Audio",
 		"subtitles": "Subtitles",
+		"channels": "{{channels}} Channels",
 		"forced": "Forced",
 		"hearing-impaired": "CC",
 		"default": "Default",
diff --git a/front/src/models/video-info.ts b/front/src/models/video-info.ts
index 506599bf..80e0466d 100644
--- a/front/src/models/video-info.ts
+++ b/front/src/models/video-info.ts
@@ -35,6 +35,7 @@ export const AudioTrack = z.object({
 	language: z.string().nullable(),
 	codec: z.string(),
 	mimeCodec: z.string().nullable(),
+	channels: z.int(),
 	bitrate: z.number(),
 	isDefault: z.boolean(),
 });
diff --git a/front/src/ui/info/index.tsx b/front/src/ui/info/index.tsx
index 8bd7377a..a78c6a2f 100644
--- a/front/src/ui/info/index.tsx
+++ b/front/src/ui/info/index.tsx
@@ -94,6 +94,7 @@ export const Info = () => {
 								? t("mediainfo.default")
 								: undefined,
 							x.codec,
+							t("mediainfo.channels", { channels: x.channels }),
 						]
 							.filter((x) => x)
 							.join(" - ")}
diff --git a/transcoder/migrations/000003_add_audio_channels.down.sql b/transcoder/migrations/000003_add_audio_channels.down.sql
new file mode 100644
index 00000000..2f5955f7
--- /dev/null
+++ b/transcoder/migrations/000003_add_audio_channels.down.sql
@@ -0,0 +1,5 @@
+begin;
+
+alter table gocoder.audios drop column channels;
+
+commit;
diff --git a/transcoder/migrations/000003_add_audio_channels.up.sql b/transcoder/migrations/000003_add_audio_channels.up.sql
new file mode 100644
index 00000000..f0d5140f
--- /dev/null
+++ b/transcoder/migrations/000003_add_audio_channels.up.sql
@@ -0,0 +1,6 @@
+begin;
+
+delete from gocoder.audios;
+alter table gocoder.audios add column channels int not null default 2;
+
+commit;
diff --git a/transcoder/src/codec.go b/transcoder/src/codec.go
index acfe8839..9c98c110 100644
--- a/transcoder/src/codec.go
+++ b/transcoder/src/codec.go
@@ -100,11 +100,11 @@ func GetMimeCodec(stream *ffprobe.Stream) *string {
 		return &ret
 
 	case "ac3":
-		ret := "mp4a.a5"
+		ret := "ac-3"
 		return &ret
 
 	case "eac3":
-		ret := "mp4a.a6"
+		ret := "ec-3"
 		return &ret
 
 	case "flac":
diff --git a/transcoder/src/filestream.go b/transcoder/src/filestream.go
index 9f9637fb..2efd7830 100644
--- a/transcoder/src/filestream.go
+++ b/transcoder/src/filestream.go
@@ -77,52 +77,12 @@ func (fs *FileStream) Destroy() {
 func (fs *FileStream) GetMaster(client string) string {
 	master := "#EXTM3U\n"
 
-	for _, audio := range fs.Info.Audios {
-		for _, quality := range AudioQualities {
-			master += "#EXT-X-MEDIA:TYPE=AUDIO,"
-			master += fmt.Sprintf("GROUP-ID=\"audio-%s\",", quality)
-			if audio.Language != nil {
-				master += fmt.Sprintf("LANGUAGE=\"%s\",", *audio.Language)
-			}
-			if audio.Title != nil {
-				master += fmt.Sprintf("NAME=\"%s\",", *audio.Title)
-			} else if audio.Language != nil {
-				master += fmt.Sprintf("NAME=\"%s\",", *audio.Language)
-			} else {
-				master += fmt.Sprintf("NAME=\"Audio %d\",", audio.Index)
-			}
-			if audio.IsDefault {
-				master += "DEFAULT=YES,"
-			}
-			master += "CHANNELS=\"2\","
-			master += fmt.Sprintf("URI=\"audio/%d/%s/index.m3u8?clientId=%s\"\n", audio.Index, quality, client)
-		}
-		master += "#EXT-X-MEDIA:TYPE=AUDIO,"
-		master += fmt.Sprintf("GROUP-ID=\"audio-%s\",", AOriginal)
-		if audio.Language != nil {
-			master += fmt.Sprintf("LANGUAGE=\"%s\",", *audio.Language)
-		}
-		if audio.Title != nil {
-			master += fmt.Sprintf("NAME=\"%s\",", *audio.Title)
-		} else if audio.Language != nil {
-			master += fmt.Sprintf("NAME=\"%s\",", *audio.Language)
-		} else {
-			master += fmt.Sprintf("NAME=\"Audio %d\",", audio.Index)
-		}
-		if audio.IsDefault {
-			master += "DEFAULT=YES,"
-		}
-		master += "CHANNELS=\"2\"," // TODO
-		master += fmt.Sprintf("URI=\"audio/%d/%s/index.m3u8?clientId=%s\"\n", audio.Index, AOriginal, client)
-	}
-
 	// codec is the prefix + the level, the level is not part of the codec we want to compare for the same_codec check bellow
 	transcode_prefix := "avc1.6400"
 	transcode_codec := transcode_prefix + "28"
 	transcode_audio_codec := "mp4a.40.2"
 
 	var def_video *Video
-	var def_audio *Audio
 	for _, video := range fs.Info.Videos {
 		if video.IsDefault {
 			def_video = &video
@@ -132,10 +92,53 @@ func (fs *FileStream) GetMaster(client string) string {
 	if def_video == nil && len(fs.Info.Videos) > 0 {
 		def_video = &fs.Info.Videos[0]
 	}
-	if len(fs.Info.Audios) > 0 {
+
+	var def_audio *Audio
+	for _, audio := range fs.Info.Audios {
+		if audio.IsDefault {
+			def_audio = &audio
+			break
+		}
+	}
+	if def_audio == nil && len(fs.Info.Audios) > 0 {
 		def_audio = &fs.Info.Audios[0]
 	}
 
+	if def_audio != nil {
+		aqualities := utils.Filter(AudioQualities, func(quality AudioQuality) bool {
+			return quality.Bitrate() < def_audio.Bitrate
+		})
+		aqualities = append(aqualities, AOriginal)
+
+		for _, audio := range fs.Info.Audios {
+			for _, quality := range slices.Backward(aqualities) {
+				master += "#EXT-X-MEDIA:TYPE=AUDIO,"
+				master += fmt.Sprintf("GROUP-ID=\"a-%s\",", quality)
+				if audio.Language != nil {
+					master += fmt.Sprintf("LANGUAGE=\"%s\",", *audio.Language)
+				}
+				if audio.Title != nil {
+					master += fmt.Sprintf("NAME=\"%s\",", *audio.Title)
+				} else if audio.Language != nil {
+					master += fmt.Sprintf("NAME=\"%s\",", *audio.Language)
+				} else {
+					master += fmt.Sprintf("NAME=\"Audio %d\",", audio.Index)
+				}
+				if audio == *def_audio {
+					master += "DEFAULT=YES,"
+				}
+				if quality == AOriginal {
+					master += fmt.Sprintf("CHANNELS=\"%d\",", audio.Channels)
+				} else {
+					master += "CHANNELS=\"2\","
+				}
+				master += fmt.Sprintf("URI=\"audio/%d/%s/index.m3u8?clientId=%s\"\n", audio.Index, quality, client)
+			}
+			master += "\n"
+		}
+		master += "\n"
+	}
+
 	if def_video != nil {
 		qualities := utils.Filter(VideoQualities, func(quality VideoQuality) bool {
 			return quality.Height() < def_video.Height
@@ -148,8 +151,8 @@ func (fs *FileStream) GetMaster(client string) string {
 		}
 		qualities = append(qualities, Original)
 
-		for _, quality := range qualities {
-			for _, video := range fs.Info.Videos {
+		for _, video := range fs.Info.Videos {
+			for _, quality := range slices.Backward(qualities) {
 				master += "#EXT-X-MEDIA:TYPE=VIDEO,"
 				master += fmt.Sprintf("GROUP-ID=\"%s\",", quality)
 				if video.Language != nil {
@@ -168,6 +171,7 @@ func (fs *FileStream) GetMaster(client string) string {
 					master += fmt.Sprintf("URI=\"%d/%s/index.m3u8?clientId=%s\"\n", video.Index, quality, client)
 				}
 			}
+			master += "\n"
 		}
 		master += "\n"
 
@@ -178,23 +182,35 @@ func (fs *FileStream) GetMaster(client string) string {
 				if def_audio != nil && (def_audio.MimeCodec == nil || *def_audio.MimeCodec != transcode_audio_codec) {
 					audios = append(audios, matchAudioQuality(def_video.Quality()))
 				}
-				for _, audio_quality := range audios {
+				for _, aquality := range audios {
 					// original & noresize streams
 					bitrate := float64(def_video.Bitrate)
 					master += "#EXT-X-STREAM-INF:"
 					master += fmt.Sprintf("AVERAGE-BANDWIDTH=%d,", int(math.Min(bitrate*0.8, float64(def_video.Quality().AverageBitrate()))))
 					master += fmt.Sprintf("BANDWIDTH=%d,", int(math.Min(bitrate, float64(def_video.Quality().MaxBitrate()))))
 					master += fmt.Sprintf("RESOLUTION=%dx%d,", def_video.Width, def_video.Height)
-					var audio_codec = transcode_audio_codec
-					if def_audio != nil && audio_quality == AOriginal {
-						audio_codec = *def_audio.MimeCodec
+
+					codecs := make([]string, 0)
+					if quality == Original {
+						if def_video.MimeCodec != nil {
+							codecs = append(codecs, *def_video.MimeCodec)
+						}
+					} else {
+						codecs = append(codecs, transcode_codec)
 					}
-					if quality != Original {
-						master += fmt.Sprintf("CODECS=\"%s\",", strings.Join([]string{transcode_codec, audio_codec}, ","))
-					} else if def_video.MimeCodec != nil {
-						master += fmt.Sprintf("CODECS=\"%s\",", strings.Join([]string{*def_video.MimeCodec, audio_codec}, ","))
+					if aquality == AOriginal {
+						if def_audio != nil && def_audio.MimeCodec != nil {
+							codecs = append(codecs, *def_audio.MimeCodec)
+						}
+					} else {
+						codecs = append(codecs, transcode_audio_codec)
+					}
+					if len(codecs) > 0 {
+						master += fmt.Sprintf("CODECS=\"%s\",", strings.Join(codecs, ","))
+					}
+					if def_audio != nil {
+						master += fmt.Sprintf("AUDIO=\"a-%s\",", string(aquality))
 					}
-					master += fmt.Sprintf("AUDIO=\"audio-%s\",", string(audio_quality))
 					master += "CLOSED-CAPTIONS=NONE\n"
 					master += fmt.Sprintf("%d/%s/index.m3u8?clientId=%s\n", def_video.Index, quality, client)
 				}
@@ -206,7 +222,9 @@ func (fs *FileStream) GetMaster(client string) string {
 			master += fmt.Sprintf("BANDWIDTH=%d,", quality.MaxBitrate())
 			master += fmt.Sprintf("RESOLUTION=%dx%d,", int(aspectRatio*float32(quality.Height())+0.5), quality.Height())
 			master += fmt.Sprintf("CODECS=\"%s\",", strings.Join([]string{transcode_codec, transcode_audio_codec}, ","))
-			master += fmt.Sprintf("AUDIO=\"audio-%s\",", string(matchAudioQuality(quality)))
+			if def_audio != nil {
+				master += fmt.Sprintf("AUDIO=\"a-%s\",", string(matchAudioQuality(quality)))
+			}
 			master += "CLOSED-CAPTIONS=NONE\n"
 			master += fmt.Sprintf("%d/%s/index.m3u8?clientId=%s\n", def_video.Index, quality, client)
 		}
diff --git a/transcoder/src/info.go b/transcoder/src/info.go
index 3860aa63..e6761b97 100644
--- a/transcoder/src/info.go
+++ b/transcoder/src/info.go
@@ -17,7 +17,7 @@ import (
 	"gopkg.in/vansante/go-ffprobe.v2"
 )
 
-const InfoVersion = 3
+const InfoVersion = 4
 
 type Versions struct {
 	Info      int32 `json:"info" db:"ver_info"`
@@ -98,6 +98,8 @@ type Audio struct {
 	Codec string `json:"codec" db:"codec"`
 	/// The codec of this stream (defined as the RFC 6381).
 	MimeCodec *string `json:"mimeCodec" db:"mime_codec"`
+	/// The number of channels that stream has.
+	Channels int `json:"channels" db:"channels"`
 	/// The average bitrate of the audio in bytes/s
 	Bitrate uint32 `json:"bitrate" db:"bitrate"`
 	/// Is this stream the default one of it's type?
@@ -280,6 +282,7 @@ func RetriveMediaInfo(path string, sha string) (*MediaInfo, error) {
 				Language:  NullIfUnd(lang.String()),
 				Codec:     stream.CodecName,
 				MimeCodec: GetMimeCodec(stream),
+				Channels:  stream.Channels,
 				Bitrate:   ParseUint(cmp.Or(stream.BitRate, mi.Format.BitRate)),
 				IsDefault: stream.Disposition.Default != 0,
 			}
diff --git a/transcoder/src/metadata.go b/transcoder/src/metadata.go
index df53eee3..4a79c912 100644
--- a/transcoder/src/metadata.go
+++ b/transcoder/src/metadata.go
@@ -318,8 +318,8 @@ func (s *MetadataService) storeFreshMetadata(ctx context.Context, path string, s
 		tx.Exec(
 			ctx,
 			`
-			insert into gocoder.audios(sha, idx, title, language, codec, mime_codec, is_default, bitrate)
-			values ($1, $2, $3, $4, $5, $6, $7, $8)
+			insert into gocoder.audios(sha, idx, title, language, codec, mime_codec, channels, is_default, bitrate)
+			values ($1, $2, $3, $4, $5, $6, $7, $8, $9)
 			on conflict (sha, idx) do update set
 				sha = excluded.sha,
 				idx = excluded.idx,
@@ -327,10 +327,11 @@ func (s *MetadataService) storeFreshMetadata(ctx context.Context, path string, s
 				language = excluded.language,
 				codec = excluded.codec,
 				mime_codec = excluded.mime_codec,
+				channels = excluded.channels,
 				is_default = excluded.is_default,
 				bitrate = excluded.bitrate
 			`,
-			ret.Sha, a.Index, a.Title, a.Language, a.Codec, a.MimeCodec, a.IsDefault, a.Bitrate,
+			ret.Sha, a.Index, a.Title, a.Language, a.Codec, a.MimeCodec, a.Channels, a.IsDefault, a.Bitrate,
 		)
 	}
 	for _, s := range ret.Subtitles {