BC Fresh, Clean, UnModded 1.1 Install Sound/Performance Issue

[marooned]

-Summary-
My install will not sound smooth unless I leave the dxdiag utility open.  Gameplay and video seems fine either way, but the sound will lag, jump, skip unless the utility is open during gameplay. 


::Update::

I finally played and completed the campaign with only a few crashes back to the desktop.


I suppose I made a mistake, pardon the trouble.