Classe' preamp ground loop hum. Help!

Is this pre-amp new? Do you have a VCR pluged into the same outlet? Also try lifting all ground except the pre and let me know what happens. Simply Music

Simply_music- The preamp is new. I disconnected everything from the outlet and all other outlets on the circuit and still got the hum. I replaced the classe w/ first an Adcom preamp and then an A/V preamp/processor and got no hum with either. This preamp has a separate power supply. I wonder if it could be a problem w/ either the A/C cord or the power line from power supply to preamp?

Lift the ground on the preamp. The hum should go away.

Narrod- Forgive my stupidity, but is there any other way to lift the ground on the pre-amp than removing the third prong from the existing power cord or getting a new ungrounded ( two prong)power cord?

Ignatz get a "cheater plug" just two ends and yor get ground free + reverse capability for testing..

Ignatz. The easiest way to do that is just go to your walmart, k-mart or home depot and buy a cheap plug-in multi plug for about $3.00 and take a pliers and break the ground on it and plug the unit you want to lift into it but may I suggest that you lift the amp first and if no improvement then the pre but not both and if that works just get a power cord and cut the ground. Now this is all assuming that the noise is there even with the volume is down and in both channels, right? I am a Class A dealer here, you can drop me an e-mail if you would like and if the problem persists and if your dealer can't help.