Hello all

Have a Canaan AvalonMiner 1166 Pro that has been losing about ~0.1TH/s per day. The boards are not overheating (62° C, 65° C, 67° C,), and the fan speeds remain under 60% (~4500 RPM). These temperature/fan-speed conditions have remained fairly constant for over a month but now the hash rate seems to be slowly but consistently decreasing. I am not clear as to what could be causing this behavior. The ASIC was advertised to get 81 TH/s, but really never performed above 79 TH/s when I first got it. For months it performed in the 76-78 range and now is around 73.6 TH/s and decreasing with each passing day.

Any thoughts? Actions I can take? Should the boards vary that much in temperature?

Thank you