Tasked by Kiwamu and Stefan to turn random knobs in a hope of getting rid of 100-1kHz bump, I was able to gain 15 Mpc by adding -0.05 offset to CSOFT pitch and yaw. I haven't had a chance to try every ASC knobs due to the power glitch. We were at 75 Mpc before the IFO went down.

Here's a note on everything I've tried (all time in PT):

3:40 added/subtracted 0.02 counts to H1:LSC-MOD_RF45_AM_RFSET -- Nothing improved

3:46 Added +6 gain to PRC1 LSC -- 27 Hz line became visible. But later found this line to come and go so this could totally be a coincidence

3:52 Changed CO2X power to 1W -- quickly dropped the power back to nominal when I realized that it's probably going to take a while to see the result

4:38-4:58 [In ASC land] Played with CSOFT pitch and yaw offset -- Settled at -0.05 for both. Slightly improved overall DARM spectrum but made 20-30 Hz wrose. Gained 15 Mpc in range here (if it's not calibration that's fooling with me). Any more negative number added would decrease AS90/POP90.

5:06 Added -10 to CHARD pitch -- nothing improved

5:13 Added -0.07 to CSOFT pitch -- nothing improved

5:14 Added -20 offset to CHARD yaw. -- Nothing improved

5:17 Added offset to DHARD pitch -- Nothing improved

5:27 Added offset to DSOFT pitch -- Nothing

5:48 Added -0.05 offset to DSOFT yaw -- Increased AS90/POP90 but no obvious approvement in DARM.

5:58 Added -25 offset to INP1_Y -- improved AS90/POP90 but no apparent improvement in DARM spectrum

6:08 Power glitch. Meh.

I also moved PR3 and changed something on SRC1 but didn't write down details (since it probably was not doing anything).

I put everything back in place before the power glitch except for the CSOFT gain that worked. I turned off all the gain buttons that I turned on except for CSOFT P and Y but not neccesary return the gain number back to what they were. I have them all written down though.