dont know anything about the sound systems of aircrafts, but why can’t they switch off each sound system one by one and see which one causes it and then see the

dont know anything about the sound systems of aircrafts, but why can’t they switch off each sound system one by one and see which one causes it and then see the possible inputs to the one where the sound is played? I assume it cannot be that hard to do during maintenance period especially if this happens on multiple planes.