sherpya has updated his Heretic port once again. The release notes:

Update, sound support added is not very smooth, but not so bad 🙂 (I think I’ll need to implement a sort of noise shaper since samples are 11khz 8bit), also a bit faster since I’ve enabled -O3 on the compiler (before was crashing with opt>01 since there is an incompatible gcc optimization)

http://forums.ps2dev.org/viewtopic.php?t=3824