OK I have a stereo mini out in my computer'a sound card (Yamaha AC-XG). I have hooked that up (via a min to RCA cord) to my Yamaha Natural Sound Stereo Receiver. This is what I use when I play mp3's through my stereo. I realized that when nothing is playing, but I have it have the headphones (V^'s) there is a constant "buzz." This does not occur when I switch the receiver over to the component DVD/CD Player. Is this the result of my sound card, my receiver, or the mini to RCA cord that I am using? When the mp3's are playting everything sounds great. Is this normal?
good chance it's electrical noise from inside the case that's being picked up. you can get some low end pro audio cards with breakout boxes that have the DAC's etc in the box and not on the card. should help a great deal in that regard.
(I'm looking at getting one myself actually - probably a m-audio delta 44)
Buzz or hum when connecting the computer to a stereo amp/receiver is quite normal. It results from an electric potential between the two devices, not from any bad component. The remedy for this purpose is a galvanic decoupling by dint of a decoupling transformer. It's not very expensive, just a small device and should be available in every electronics store.