Sound

Sounds like a cable problem. I get this a lot with my coaxial cable, it takes a little turning or playing with to start working.

Use an optical cable if you have the option, they are more secure, or if you don't mind going analog use the red white rca cable.

Either that or replace the coaxial, if you're using one. If your amp/TV, whatever you're connected to, has a vacant audio input jack to switch to, try that as well.

Good luck