Mac, I'm researching things and I come across a ground loop isolator at musiciansfriend.com. It's about $70. One reviewer says this ...

Great for killing ground loops. NOT A NOISE GATE. Plugged it in between my amp and my loop station and it instatly stopped the buzz. If you do not know the difference between a noise gate and a hum or buzz eliminator, do some research before you buy.

I have found that hum and buzz eliminators are one in the same. I have not found this, "noise gate" that he refers to.

Also, I found another device that just plugs into a wall outlet ... Click Here

With this device however, the product description warns of using other "filters" and so that concerns me. It reads ...

You no longer have to run your audio signal through filtering that results in loss of volume, tone, or both. Some devices simply remove or float the ground, which is never safe!

Your comments please. And thank you for your obvious expertise in this area.

Ike