Originally Posted by RonaldDumsfeld
Bite the bullet, accept you bought unwisely and start again. Never go back(wards).
Indeed. Do not throw good money after bad.
And "noisy" USB? If the device is USB-powered, it's a ground loop. If it's powered separately, then you've a bad cable in the chain or heavy RF/EM interference.
USB deals strictly in digital streams--lots of 1s & 0s, not an analog waveform. Mess up that digital bitstream, and you get very noticeable glitches, not noise. It's very much like a satellite TV transmission: When the signal is good, it works. When the signal is interrupted even momentatily, you get blocky video & glitchy audio.
Personally, I prefer USB over optical & coax. With a USB connection, you get the shortest path and least processing to get out of the system (CPU > southbridge > USB), whereas the on-board audio tacks on the internal audio codec, and an add-on card adds the PCI(e) bus and it's codec before leaving the system.
As far as cables are concerned, I just used the 1m USB cables that Dell ships with their monitors--they just happen to have a choke at one end to combat interference.