Some static, but I am still on analog cable TV and see the static on some stations as a result of that. The first thing I did notice though after watching the TV before, then installing the Panamax and watching after is that the images did look clearer, well, as clear as the analog feed can provide. I still see ghosting on a couple of the analog channels.
I did not have ground loops, before nor after. These can be caused by bad cabling and most often by improper grounded cable/sat feeds. I know my cable system is grounded about 600 feet from where my electical is, but this does not cause a ground loop in my case.
If I went up close and put my ear near my speakers, I could always hear a 60hz hum, but only if I was close. The audible level of this hum seems to have dropped enough for me to notice.