I found my original 800xl from when I was a kid in the garage. Did not have a power supply so I picked up a 61982 off ebay. When I turn it on I see scrambled video and hear a buzz. This happens when I use the RF out and when using composite out via the monitor port. I recently had a similar issue with a 2600 and swapping out the TIA worked. Could this be as easy as replacing the GTIA or does the buzzing indicate another issue?