I've read of DVI switches and cables adding "sparkles" and affecting picture quality. How is this possible if DVI is a digital transmission medium? All digital mediums that I know of include checksums, etc... to correct for or at least detect errors in transmission. It's possible to destroy bits but not to change them. If that's the case, then I'd think that a DVI cable/switch would either pass signal or not, but it shouldn't change it... right? Wrong? Beuller?