You say there's "static" when the volume is up and there's no signal?

After checking the CD player on another input, also maybe check what else is on the same circuit and the grounding of the outlets you're using... may be interference from, say, a water cooler, or ground potential difference... possibly RFI/EMI if you've run any wiring near noisy areas (AC, fluorescents). Most of that would show up as hum, though, not static.

Bren R.