My system for tv and radio is: Shared dish in apartment block 2 coax to Humax Foxsat HDR into a Yamaha RX V467 AV amp interconnections by HDMI cables 5 speaker surround speakers plus sub Problem is: Audio on TV HD channels is fine Audio on radio and non-HD channels is suddenly non-existant I've checked and re-fitted the coax to the Humax and all other connections with a squirt of contact cleaner No settings have been altered. Any thoughts anyone please ?