fix: use ADTS for AAC transcoding, temporarily exclude AAC from transcode decisions (#5167)

* fix: use ADTS format for AAC transcoding to avoid silent output on ffmpeg 8.0+

The fragmented MP4 muxer (`-f ipod -movflags frag_keyframe+empty_moov`)
produces corrupt/silent audio when ffmpeg pipes to stdout, confirmed on
ffmpeg 8.0+. The moof atom offset values are zeroed out in pipe mode,
causing AAC decoder errors. Switch to `-f adts` (raw AAC framing) which
works reliably via pipe and is widely supported by clients including
UPnP/Sonos devices.

* fix: exclude AAC from transcode decision, as it is not working for Sonos.

Signed-off-by: Deluan <deluan@navidrome.org>

---------

Signed-off-by: Deluan <deluan@navidrome.org>

server/subsonic/transcode.go

@@ -268,6 +268,16 @@ func (api *Router) GetTranscodeDecision(w http.ResponseWriter, r *http.Request)
 	}
 	clientInfo := clientInfoReq.toCoreClientInfo()
 
+	// TODO: Remove this filter once AAC transcoding works reliably
+	// with streaming clients (Sonos, etc).
+	// See https://github.com/navidrome/navidrome/discussions/4832#discussioncomment-16068231
+	clientInfo.TranscodingProfiles = slices.DeleteFunc(clientInfo.TranscodingProfiles, func(p stream.Profile) bool {
+		if p.AudioCodec != "" {
+			return stream.IsAACCodec(p.AudioCodec)
+		}
+		return stream.IsAACCodec(p.Container)
+	})
+
 	// Get media file
 	mf, err := api.ds.MediaFile(ctx).Get(mediaID)
 	if err != nil {