Humming noise in speakers

If it is an "electrical" hum the problem most likely is a ground loop. Try getting one of those three prong to two prong adapters (often called cheater plugs) from the hardware store. Plug your preamp power cord into it and then into your power source. What we are doing here is "floating" the ground on that piece of equipment in an attempt to reduce or better yet, eliminate the ground loop causing the hum eminating from your loudspeakers. If this doesn't work try floating another component and so forth until the hum stops.

Good luck.

I agree with the adaptor. You can also try to reverse the adaptor. Just turn it 180degrees in the plug. Honestly though, once I got a decent line conditioner, I have never had this problems since.

Elevick:

Which conditioner solved the ground loop problem? I don't have a conditioner yet but run into the occasional loop gremlin.

Jeff