hit help: my radio used to shut off when played loud but now it comes on - Help.com

you were probably turning it up too load and shorted it out or blew the speakers.

It sounds like vibration is triggering the shut down. There must be a loose connection, like with the batteries or the line cord if it is plugged in. Just suspect something loose and with the radio turned on, move the cord or just tap the radio and see when it goes off. It may be on the inside, like a break in one of the traces on the circuit board if the radio was ever dropped. The break would most likely be near a corner on the circuit board.

If the radio plugs into the wall, then be careful of electrical shock if you open it up. Or, if the radio can also play on batteries, then use those to run the radio and see if the problem still shows up. If so, then it’s not the plug or line cord. And it would be safe for you to open up on batteries.