Is there a problem with XM and IT music files running in Blitz3d
There have been prior bug reports... seems Blitz inherited a bug in an FMOD revision. Of course FMOD was fixed pretty quickly but BRL has been a tad busy recently (with some sort of "Max" thingy); while you wait for the fix to be patched in you might try using Modplug tracker to convert your XM/IT to S3M... I think that format still functions properly but I'm not 100% certain.