About plug-in:

You can find here a TMC plug-in for XMMS (linux program very similar to WinAmp) written by adept_zap. With that plug-in you will be able to play .tmc and tm8 files using XMMS. .tmc and .tm8 files are files produced by program called Theta Music Composer (written by Marcin Lewandowski on Atari xl/xe computers). Plug-in is free to use and distribute.