It was noticed that filter cavity z-correction was feeding back some high frequency components recently.
I modified the filters and now less high frequency components are feed to end mirror.
The new filter is called dc_damp2 (gain is adjusted so that we can use gain 1 in medm). Let's use this filter in the future.
Poles: 1e-4, 0.1(1), 20, 20, 300
Zeros: 0.04, 0.05(1), 3
The comparison of signal sent to end mirror is attached.