Can I ground my preamp?


I have monoblocs each w/their own grounded cord and a preamp w/o a grounded cord. The problem is that I'm getting a slight ground hum from each amp. The amp manual says if this happens to use a cheater plug on the amps and to ground "at least one other component." Is it possible to ground my preamp, and if so how? Many thanks for any advice.
bojack
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I had a hum problem with a pair of monoblox and got rid of it by running a wire from the preamp chassis to one of the amp's chassis.
Wow, this is more complicated than I thought. I think I will try your suggestion first, Stingreen, to see. BTW, the amps are the only grounded components (CD, DVD, and preamp are all non-grounded). Am on work travel, but I'll report back when I get a chance.
If you are having a ground loop problem you can drop the ground on your amps and leave the rest alone. You don't have to ground any components.
Tvad,
I do have have Ground Zero and used it in various system configurations. It definitely works, but requires quite a bit of fiddling, and in some cases is not 100% effective.
I have to admit though, I probably didn't have enough patience to follow the protocol to the last letter.