MP3gain is really very, very different to the Hijack auto volume. The auto volume stuff can introduce all sort of nasty artefacts (it really doesn't like The Police - Don't Stand So Close to Me).

It also levels the volume within tracks, MP3gain doesn't do that in any cases.

BTW I still use the auto volume in car, it works well in car as long as you accept the occasional oddity like Don't Stand So Close to Me.

I am a bit embarrassed that I ported the auto volume stuff to the Rio Receiver, don't know what I was thinking about thinking that would be a good idea !