I had to check this plugin out: yes, it is here -
http://www.eisenlohr.org/xmms-crossfade/index.html

I compiled it, installed it, tested it - and now I'm back with XMMS again. Perfect gapless playback!
I really do prefer XMMS to all the other players.

I still use, and like XMMS too. But it does not do gapless, and quite by chance I discovered that flac123 does. That does not help with MP3, of course. But I did some research and found a player called Aqualung which claims to do gapless MP3 -- and it does! It can also be controlled from the console so it just needs to run in the background and I can send files to it and play them from the command line.

By the way, I convert flac files to MP3 with this :--
  for i in *flac; do /usr/bin/flac -dfcs "$i" | lame -h -V 5 - "$(basename "$i" flac)mp3"; done

As a classical music listener, gapless playback is very important to me. Most of my music is in FLAC, and I have found that the command-line player flac123 is perfect for my needs; gaps are completely inaudible.

Unfortunately I still have quite a large quantity of music in MP3. I did not encode these - they have been obtained from many sources. I generally use mpg123 to play these, bit it is not gapless. Does anyone know of a player - preferably for the command-line - which will perform gapless playback of MP3 files?