I can not confirm rolling back to 1.2. If i try to, controler board stays in DFU mode (red LEDs).
I did those steps:
./opt/scripta/startup/miner-stop.sh
python /usr/bin/update_fw.py
python reset_stm.py
lsusb | grep 0483
What does this command show when you run it?
lsusb | grep 0483
Either there's nothing, or something with "STMicroelectronics" in it.
Same question as to chup: What was the last firmware you successfully flashed (the one I posted? flexmeister's? One of the stock images?)