i'd double check the firmwares md5 you downloaded and make sure its compatible with your chipset, then make sure they are not knockoffs chips. finally i'd double check the transmitter and make sure its up to date too. all 4 failing indicates a major problem, although what exactly is going wrong i can't say with certainty.  aliexpress black friday sales have already begun. lots of drone frames, motors, flight controllers, batteries, ect. on sale.
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