The FFMpeg wiki has some information, including calling out its own "vorbis" encoder as sub-par and not recommended (but apparently they also support a different "libvorbis" encoder that does not suffer from problems?) See https://trac.ffmpeg.org/wiki/Encode/HighQualityAudio
Also for AAC in particular there are a few options https://trac.ffmpeg.org/wiki/Encode/AAC
Whoa, I'd never imagined that could be the case and appreciate the heads-up. I've only had experience with the Apple and Fraunhofer encoders so far.
Mind calling out the offender(s)? This summer I'm releasing a best practices guide (and hopefully tools) to help podcasters move to AAC, and that would be useful to mention.