Over the last week, it seems many people, including myself, have developed this little redirecting virus when using Google (or Yahoo, it seems).
Try a Google search for anything, and watch the Status bar on your browser. See if it looks for the IP "188.8.131.52". If it does, congratulations; you have the virus too! It redirects your search results (and it may be why my Firefox crashes a lot lately then won't find anything for about 10 minutes even after flushing DNS and everything).
The fix appears to be removal of C:/Windows/system32/wdmaud.sys (note, NOT C:/Windows/system32/drivers/wdmaud.sys). Unconfirmed, but another site suggests also removing the file "sysaudio.sys" from the same folder (as again, the real "sysaudio.sys" is in the "drivers" subfolder).
And you know, I think I remember trying to play a MIDI file from some site that ended up not playing, with a "corrupted" error... and that's when it began for me. Makes sense, since wdmaud.sys is used in MIDI rendering.