1. Get out the canned air and give all the ports and cables a shot on contacts.
2. See if the firmware is current in the HT.
3. Try stereo or PCM for the audio source.
4. If that fails, make it a warranty issue. Return it if the maker can't resolve.
I have the HT-F5550 surround sound, and every 10 minutes or so the audio cuts out for about 2 seconds (pretty annoying) it never used to do this, happens whether i am connect to the tv (hdmi) or the ps4 (optical) any help would be much appreciated. Maybe I need a software update.