Recently received a S9 from the January Batch. Right away I was having issues getting all the card to hash at full power. The S9 was flakily only recognizing 1 or 2 of the cards each time I would start it up. I was only getting around 5,000 - 10,000 GH/S because of this. It was never consistent, each time I would boot the S9 up, different board would be hashing.
My S9 was being powered by the Bitmain 1600w power supply and was hooked up at 120v on a 20amp breaker. From the kernel Logs I was able to see that one the chains was not recognizing all the cores. The error message was something like:
Chain [J6] 0 cores
Tried to reset the s9 many times and updated to the latest firmware. I went through and only hooked up one board at a time in the S9 and was able to confirm that each board would hash individually, without the others connected.
The Solution:I hooked the power supply up to 240v and I have been hashing at full power for 2 days straight now.
TLDR;If your S9 is acting flaky and not hashing all cards consistently. Try switching to 240v