Hi, I have the same problem also. Noisy click click crackle on ADAT input one (channels 11-18). ADAT port 2 is fine. I have also tested my ADAT source via it's analogue outs and the signal is fine, and its' ADAT out into the quantum ADAT port 2 is fine. I have tried all possible combinations for the word clock. makes no difference. I have raised a support ticket also. Hopefully there is a simple fix.