FFMPEG version vs audio quality

[simoncn]

For some reason, this SynoCommunity build of FFmpeg refuses to open an AAC-encoded audio stream. I have tried enabling extra diagnostics but there is no message giving a reason for this. Instead, you can use builds from this website, which work correctly with AAC-encoded audio.

For mp4 and aac transcoding, an external converter program (ffmpeg) is always used. The comment about removing the semicolon to use the internal converter applies only to FLAC files but this is not made clear. I will reword this section to clarify this.