First, unplug the RCA connectors at the amp connection. Turn the amp back on and see if you still get that noise. If the noise is still present then double check your ground connection. I assume you are pulling power directly from the positive battery terminal. If that still doesn't work, see where the gain controls are set on your amp (they may be up too high). Lastly, if the noise is gone when the RCAs are unplugged and present when the RCA's are plugged in then you have traced the problem to the head unit and/or cables. Run another set of RCAs striaght from the head unit to the amp (not under the carpet). Check for the noise. If the noise is there then it's your headunit. You will then have to double check the connection on the head unit and then check the settings. Is the noise present even if the car is not running but the radio is on (key in acc position)? Keep me posted.