After checking for attenuator settings and squelch and RF gain settings.....

Has the radio been left connected to an antenna during lightning? Might have to follow in the input traces to find an input diode blown out or something.

I found a blown diode on my SW receiver by touching the traces with my fingers while it was on and got signal from my hand on one side of the diode but not the other.

(gotta love low voltage equipment - would never use my fingers in my old tube rigs)