We don't know this either. An automatic switch-off often has one of 2 causes: Thermal shutdown; if the appliance gets too warm (are the cooling slots open?) or a short circuit (however small) on the loudspeaker cable. If this occurs during continuous operation, it is often the former. If it occurs elsewhere, it is often the second.

I am not familiar with this. With DAB reception, however, it can happen that a station cancels.....Adjust antenna better