I have 91 such miners and im getting day by day more and more disappointed for weeks now.
Lot of details missing, miner freezes, no chance to know which one from looking at the lights, only one firmware update so far, expected for weeks another one but nothing yet.
Lot of restart needed and most of miners need a manual restart (power off / on) to get back. if you are lucky miner runs again for another few hours until it freezes again. In most cases another forced reboot is needed.
Hashrate acceptance is very bad on almost all pools. Even on BW it self.
I hope my post wakes up some of those from BW and HB representatives.
I have sent few times printscreens, videos etc but the reply is: BW team isnt getting the firmware out.
This brings lot of questions for hyperbit, but i will wait few more days, even it is causing is so much damages.
Unfortunately, we all seem to be in the same situation. I'm having lots of problems with my miners. The L3+ is MUCH more stable and productive IMHO. I might add that the BW.com website has now listed the L21s for sale. I am not sure what the status is of the former distributor, but they are not answering our messages any longer.
When I unpacked my miners, I could see that they had been running for 187 days previous to arrival at my house. See picture.
https://imgur.com/a/vre7Bwow thanks for posting that! Sorry you had this happen to you! How dishonorable