Can't get no satisfaction from Comcast

About two weeks ago, i had comcast come out and install digital for my tv and phone. On the fourth day, when hanging up the phone, which was connected by the comcast service person, right next to the tv, the tv went black and started emmitting a loud shrill sound. I immediatedly grabbed the phone and called comcast. I was on the phone about 2 minutes when the phone started to go out, too. I was without a phone for 2 days and am still without a working tv. After many calls and visits from comcast, i was finally told that i have to "prove it is their fault" before they will do something about my tv. i had no problem until the digital was attached to the tv and phone. Both went out. When the repairman came out about this problem, the first thing he did was change some wires and connectors. Was something wired wrong? How is that my fault???.