So I may have found the culprit, but now there's a new issue... I found a capacitor I suspected to be the issue. Upon replacement, the trace was way off the top of the screen and could only be moved onscreen by turning the vertical control all the way to the end. It was also quite fat. I figured there must be a connection issue with the vertical module, which I had to remove to access the capacitor to replace. After removing, checking, and reseating the vertical board (and associated connectors such as the channel 2 coax and vertical deflection wires) there's a high frequency buzz that sounds like the high voltage power supply. This was not there before and I'm not sure of the cause, or if turning the scope on for long could damage something. Anybody come across something like this or have ideas of what to check?