issue is the now missing libavutil/audioconvert.h from ffmpeg. the fix/patch is there in 1.0.29-r1, but it's not marked stable yet. please stable 1.0.29-r1 or 1.1.1.
alsa-plugins-1.1.1 is pulling in alsa-lib-1.1.2 ~amd64
yep... marking 1.0.29-r1 should be enough w/o needing to pull any other deps.
the fixed version was stabilized