Heads up to anyone who uses these Extron units in their setups.
I have two of them, one that I purchased because the first one I had stopped working. I opened up the first one and tested the caps, but didn't find anything wrong, so I set it aside and just recently got it out to see if I could fix it.
After disassembling the power supply and starting to test the MOSFETs and stuff, I found that there is a small sub-assembly attached to the main power supply PCB which had a few components covered in that old brown glue they used to put on electronic parts to keep them in place.
If you do a lot of repair work, you probably already know that this brown glue starts to break down and it becomes hydroscopic with age. Once that happens, it will absorb moisture from the air and corrode all kinds of things.
Luckily, I caught the corrosion before it was too bad. However, I was certainly getting a high resistance short just on the surface of the glue. This was definitely the issue.
Additionally, there was a single 10uf, 50V capacitor electrolytic cap on that sub-assembly PBC that was held in place by glue and also covered with heat shrink tape for some reason. It tested high ESR and I replaced that.
Putting it back together, it's now functioning perfectly again.
I checked the inside of my other VSC700, and it has a completely different designed PSU. So my guess is that the one with the brown glue is an earlier unit. The newer unit I have with the other PSU seems to just still be working fine.