Albert Kim has posted a video reporting that there seems to be a high likelihood that SPI based ELRS boards (more likely the ones with the F411 MCU’s) can interfere with the ESC flashing process if your radio is turned on and connected to the SPI receiver.



Is this the case? Not sure anyone has examined at the code level why this happens but probably the CPU is being overloaded with tasks due to the onboard SPI receiver.

Switch off your radio while doing any flashing of firmware on your FC or ESC.