y wont WMP use my sub?

[CrashOveride]

i have onboard sound... 5.1 surrond sound... my sub is never used by WMP why is this? my freinds is used with hsi suround sound (he has Audigy)... but not mine! is this WMP? or maybe drivers? what? it dose work in games just not playing MP3s with WMP damned microsoft!

edit ok nvm... no games i tried use the sub or rear speakers either! but the little speaker test thing with the software that comes with it dose use them correctly