To check if the MC alignment is OK or not, we tried to lock the Y-arm.
Once the alignment of Y-arm was restored, we saw the resonant peak of ~0.2 in TRY.
After a small tweak of PZT2, TRY has got improved up to 0.7.
Kiwamu made a small tweak on the problematic PZT1, then the full (1.0) TRY was recovered.
Thus we concluded the current MC alignment is good enough.