You can try a "high" quality dimmer, like the Lutrons that were mentioned. Or check to see that the lighting branch circuit is on the "other" leg of your service. Not the same "leg" as your amp, or branch circuit. If these suggestions to not help, you can buy a rheostat style dimmer. These are used in medical MRI's to dim the lights down with the sensitive equipment. Most require a deep two gang box, and can generate some heat. Good luck!
Amp "Hum" caused by dimmer switches
I just recently got an Acurus 100x3 amp to drive the front 3 speakers of my home theater system and I am disapointed to find out that my room light dimmer switch is causing a very noticeable "hum" that can be heard from the listening position when no audio signal/ low passages are present. I did not have this problem using the amp in my harmon/kardon receiver. I do not want to remove the dimmer and go to an on/off switch and do not have the money for a power conditioner. Am I out of luck and have to resell the amp? I bought it used from this sight so I can not return it. The amp sounds very nice when the lights are not in use. I'd love to get some sound advice! Thanks!