Video conversion produces no audio (MP3)

[Stephen Angelico]

I have been converting videos in various ways, using a few different profiles, but It seems that in 2.2.0-pre2 (packaged in Ubuntu 14.10) and 2.2.0-rc2 (currently in Debian Jessie and Ubuntu 15.04), converting a video does not attach the sound to the output. I have used "Video for MPEG4 720p TV/device" and "Video for Android SD High". At the moment, my workaround is to fire up a Debian Wheezy VM and use VLC 2.1.5, which works just fine.
I have noticed that both profiles use MP3 audio. Is it possible that the version of libmp3lame in Jessie, Utopic and Vivid broke something, or is it VLC 2.2?