As part of Roberts ongoing work to look into the affects of the HVAC on DARM (Most recent WP11504), they noticed that their changing of the supply fan configurations started to show up negatively in DARM. There were ~4Hz peaks and consequnce harmonics seen visible in our DARM FOM on the wall.

They started this work at about 2234 utc. We lost lock at 2252, but doubtful that this was the cause of the lock loss.