My Infinity TSS-1100 subwoofer emits humming noise when I connect an input cable. It even hums when the cable is not connected to my receiver. It is silent when I remove input cable. I opened the amp and found out C71 burnt out and C72 almost blown. I replaced C71, C72, C73 and C74. However, the humming noise persists. Any idea which other component should be replaced? Thanks
Audio Players & Recorders - Infinity - TSS-1100 System