What was found
THE CREW HAD REPORTED THAT THE CABIN AUDIO WAS INOPERATIVE. TROUBLSHOOTING FOUND THE INTERNAL FUSE IN AMPLIFER OPEN AND THE SUBFOOFER NON-FUNCTIONAL. THE FUSE IN THE AMP WAS REPLACED ALONG WITH THE DEFECTIVE SUBWOOFER. THE NEXT FLIGHT THE CREW REPORTED THAT THE CABIN AUDIO WAS NOT WORKING AGAIN. TROUBLESHOOTING FOUND THE SUBWOOFER NONFUCTIONAL AGAIN, THE AMPLIFIER WAS FOUND TO BE DEFECTIVE AND WAS DAMGAGING THE SUBWOOFER. THE AMPLIFIER AND SUBWOOFER WAS REPLACED, FUNCTIONAL CHECKS WERE SATISFACTORY.