One of the goals I had when I converted my garage into a cinema room was to not have masses of cables all over the place. So, I was more than a little disappointed when I plugged my sub-woofer into the nice phono wall plate and got a very noticeable, quite loud, constant hum. So, I got my old 20ft interconnect out and have been living with it dangling from one of my speakers and working it’s way down the side of the room to the corner the sub-woofer is location.
I stumbled across something called a “ground loop isolator” when browsing the web recently. I searched for one on the website of my new trusted supplier for obscure electronic/computer gear, CPC; And for just under a fiver (£5) I found one, so I figured I’d get one for that price. I also ordered a couple of Raspberry Pi’s to get the free postage. I figured …. “why not”!
After soldering the coaxial cable which I hid in the wall back to the wall plates, I plugged it in with the isolator in-line and the hum was gone.