In order to check if ISC actions could help in the survival of the CARM null 1f step we have checked and tuned:

- SSFS phase and gain (tuned)

- PR tx and ty phase 

- B2 8MHz (input beam alignment) 

- SR alignment behavior

- DiffP set servo

None of these actions helped in reducing the drop of the sidebands

We tried also a lock acquisition with the SR misaligned -2urad in ty. No effect.