Went through the checklist & found a few items:

There was a power strip dangling inside one of the PSL racks with a signal analyzer & scope connected to it.  They were both OFF, so I removed them all from the rack.

When checking the H1 PSL, went through the procedure & for the Make Up Air it was at 100% already.  So I took it to 20% (wondering if this was ON, but Patrick mentioned that maybe this is a glitch with the interface [i.e. it displays 100% even though it might have already been at 20%].  Regardless, I took it to 20%).

Curtains on the Oplev pier adjacent to HAM4 (but I believe this might not be used anymore).