glad you had made the effort to test this, cause I'd never figure it out since I only have a WinTV PCI to work with and it works fine as far as I can tell, plus, I've never used that input on the back of the WinTV.. if you guys want to avoid this issue, I'd say you should simply use another input line for the XM.. say for instance the AUX or CD-IN that is normally found on the motherboard/soundcard -- I discourage using the Mic-In (poor quality).