Slight hum from speaker

[justphil]

I believe I am getting a slight ground loop hum from my Foster amp. I have it plugged into the same outlet my receiver is plugged into. The hum is there whether or not the RCA connection is made to the receivers LFE output. Turning up the volume on the amp doesnt increase the hum either. Is there any way to counter act it or is it norrmal for there to be a slight noise coming through when the amp is powered on? It isn't very loud but annoying all the same.

[Greg Plouvier]

Is there anything on top of, under or in close proximity to the Foster? Also try moving it around while it's on to see if that changes the hum.

[Bill Fitzmaurice]

Hum with otherwise properly configured systems is usually caused by the TV cable, which adds another ground loop source. Use a cable isolation transformer to fix it.