Speaker Interference

I have a 20" iMac connected to my home stereo system. There has suddenly started to be some weird sound interference that comes and goes every few seconds. It is not steady, it comes and goes at a really weird pace. I have tried plugging some Klipsch speakers into it and the interference is there too.

I rebooted the computer, sound is still there. I tried using the iMac built in speakers, sound is still there. I have a 23" ACD connected to it as well as a 1TB LaCie drive. I also have an iPod and three iPhones connected but none of these are the cause. Anyone have any ideas?

it sounds like you have electrical interference. if you have cable tv then make sure it is properly grounded. i can't tell you how many times cable is found to be the guilty party when this happens. to see if it is something on the line you are plugging your mac into if you can get an extension cord and plug you mac into a plug from another room and that is not on the same breaker and see if the sound goes away.

Thanks. I checked every connection and though everything seemed to be firmly plugged into the computer, the interference went away shortly after. I had no way to find out what was causing it.