We were stable at POWER_30W for a while, then we tried to go to LOWNOISE_ASC. A pitch instability rang up. I could fix it by changing DHARD_P gain from -42 to -60 and CHARD_P from 0.6 to 1.

I suspect CHARD is the culprit, since we changed the blend filter for the QPDs reducing the gain by 10 dB.

I did not put the CHARD and DHARD changes in the guardian, but the -10dB change in the CHARD_P blend is in the filter.