i just had an idea. let me know if you guys think this might help. what if i were to power the amp off of the psu (sounds like a bad idea at first, maybe it is just to late and i am not thinking clearly). The amp is small. it is designed to be able to run on a motorcycle so it doesn't take a lot of power. I was just thinking, it would eliminate any power fluxes and ground loops that could be introducing the noise. of course if i did that i would have to find another way to power the monitor. it did come with a power adapter for the car. it might be worth the try if it would knock out the noise. what do you guys think. does the p1900 even have enough juice to power something like this?