Power the cable box down, replace cable wire, replace any splitters or barrel connecters you can reach, verify all connections, power up. That normally corrects most problems, if not, you may need a service call.
I have a problem with my Samsung TV's audio falling out of sync, even with on board apps. A full power cycle by pulling the power cord out and waiting 10 seconds before reconnecting is needed. I didn't know it was a known problem. Any work arounds? I checked and there were no firmware updates available.