Trying to switch to libav. This is the last media-sounds/ffmpeg left. Can libav work for beets?
Did you try it does indeed work with libav?
Upstream beets uses ffmpeg binary directly[1]. Considering upstream dependencies are possibly pulling in gstreamer, conversion to gstreamer pipeline might be best solution but needs upstream work. For what it's worth current beets probably works with libav but this is definitely not a long term solution since it would break even with small changes of commandline arguments in libav (which libav upstream was planning last time I looked into it) https://github.com/sampsyo/beets/blob/master/beetsplug/convert.py