FOCBOX not powering my receiver

Hello, I have encountered an issue with my focbox where it no long seems to power my ppm receivers. I have tried with three different onces now. It powers them up for a second then the light goes out and they wont power up again. I just purchased it and it was running well for a few miles so I am not sure what went wrong.

Will the RX still power up if you connect them to a different focbox? Or different power source? Check voltage coming from ppm

I once had a Vesc that would power receiver but wouldn’t send a signal…so the remote would bind normally and seem to work but didn’t…it was infuriating

Seems as if the focbox is burning out the receiver, possibly faulty ppm voltage

I somehow burned 2 receivers just by plugging them in idk what i did wrong