I have a M1000e and my all of the fans run at full speed all of the time. Currently I only have 5 m600's running. I cannot find any indication of error and all of my firmware is up to date. If I reboot the whole chassis the fans will run at normal speed for a few minutes. Also if I remove one of the PowerConnect M6220 Switches from the enclose, the fan speed will return to normal. Any ideas on how to fix this issue?
Is that switch working properly when inserted back in the chassis? Have you tried swapping M6220 locations? I would also make sure M6220 firmware is up to date, there have been times when incorrect fw has caused these kinds of problems.