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
You can run a wire from your preamp. either the ground post or one of the screws holding the case, to the center screw in your AC receptacle. Sometimes this helps, sometimes not.
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