Based on some guess I had about the oscilloscope voltage of the IR transmission increasing, I set the Threshold to 10x the value of what I wanted it to be (500 mV -> 5V). I tried to check if the oscillating lock point was due to the gain being too high causing control loop resonance to appear in the cavity length, but somehow by just touching the gain knob I was able to get the SHG to lock normally. Output green is 250 mW which is nominal.

I realigned the MZ to GRMC to get good mode matching. Not much issue. I checked the error signal and the base level has some large 1 Vpk oscillation at about 8.7 kHz. The spurious oscillation seems to be coming from the output of the GRMC mixer in the "cable management box" - the spectral peak is not present from the L input (GRMC DEMOD DDS2 DAC2) or the R input (GRMC REFL RF). It also wasn't present in IRMC ERR or OPO ERR. It was getting late so I didn't have time to check if it was bad connection or some other reason.

The PLLs managed to stay locked for 32 hours. So it seems not much problem there. But I did notice that on one occasion tapping the cables for the GRMC problem above cause a bit of noise to show up in CC.

I turned off the lasers.