I just checked and there is no under voltage notification.
I just pushed an update for the ControlBlock driver. The four-player feature should work again now!
Sorry for this bug!
@michael40475 You could do the same way most people do here: burn a clean Retropie image into another SD Card, put into your RPi, put your games on it and enjoy.
problem seems to be solved - thank you all!
until next time...
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