I just got a Bolt myself recently, after my series3 HD finally gave up the ghost. I really like some of the new features. One I just discovered was, if you're on a TV show in standard def, but an HD version is available, you can press the "D" button on the remote to automatically switch to the HD channel of that show. Nice trick.

Your description of the need to disconnect and reconnect the cable TV coax line to solve problems with the signal does indeed sound related. It makes me more even more suspicious that that line is not properly grounded.