After a lockloss with no known cause this morning we had two locklosses in the final CARM offset reduction step (called resonance), because the SRCL loop rang up at around 80 Hz and tripped BS ST2 ISI. (screenshot attached).

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The SRCL gain was increased in the guardian in the step called "CARM offset reduction", there were comments that the gain increase didn't seem necessary.  We measured again today and it seemed OK to skip the gain increase, so I commented this out.  The guardian was later lowering the gain again for low noise, so the final state of the SRCL loop isn't impacted by this change. The next lock I didn't see any signs of a ring up like this.