Hi Buddy,
Are you still active here? I enjoyed your videos on repairing the 520SE. I recently acquired one that seems to be in pretty good shape, but the radio seems to have similar issues to what you fixed in your videos. I'm just starting to look into it and wondered if you were still doing videos like this somewhere else. It's helpful to see how you do the troubleshooting and repairs.
Hope you are well,
Bzimm