Hey Guys. Hope I'm not too late to jump in on this topic. I have experienced the same thing, with the result of killing several (expensive!) Happ USB trackball interface boards. My setup: homebuilt MDF cabinet, 27" Samsung TV (with picture framing matt for a bezel), Happ 3" trackball, Tornado spinner, 4 way stick (with i-pac), and X-Arcade 2 player panel. The X-Arcade panel is mounted furthest out from the TV, with the 4-way, trackball and spinner in a line across between it and the TV. I use the front button on the TV to turn it off an on. This requires reaching over the trackball and spinner to touch the button. I would get the same usb/windows 'be-bunk' noises of usb devices disconnecting occasionally (static from tv going down my arm to the spinner and trackball). In addition, the up/down axis of the trackball has stopped working (and works again only by replacing the board in the trackball). What tipped me off was when I created a lexan bezel for the TV (a flatscreen - so the bezel was almost touching the screen). The static buildup was CRAZY. I've made things better (but not perfect yet) by running a strip of tinfoil (a conductor) around the edge of the screen and grounding it with a wire to the third prong in the power bar. This runs under a custom bezel cut from the picture framing mat (nice because it is black with a red visible core). In addition, I've changed the trackball from usb to ps2 (an experiment to see if it helps) and run a ground wire from the trackball to the computer case. This has stopped the usb random disconnects, and touching the tv screen produces MUCH less static. Hoping it will also mean no more replacement boards for the usb trackball.
So in short:
I recommend the ground loop for the tv screen (couldn't find any info on anyone doing this before - so with some trepidation for life and limb, I tried it to success).
Ground the trackball to the pc.
Worked for me so far, and I'm interested in any other suggestions from there.