When mute the system I lose all sound and get get it back

I assume you mean you CAN'T get volume back afer hitting MUTE on the remote. I also assume you have tried to hit MUTE again, and INCREASE VOLUME and they also do not work. Easiest first try is to change remote batteries and clean battery contacts, and cross your fingers. If you are using a programmable Universal Remote, you may need to try an alternate programming code ... sometimes the wrong code allows some functions to work and not others. If you can get your hands on a second remote, try it again and if it works, then your first remote is broken. If not the remote, as a guess it sounds like the mute circuit is latching-up (the electrical equivalent of a stuck switch). This can be caused by anything from a bad transistor (or IC) to a bad capacitor to ground on the mute circuit. If you can locate the mute circuit on the board you can try replacing these parts (a transistor or capacitor are probably inexpensive enough to try - an IC is probably not worth it, and you will live without the convenience of a working mute). You can also try to reheat the solder joints on the circuit board for the Mute Circuit section of the board -- just re-liquify the solder and get a shiney connection. If you have a bad connection or cold solder joint it could cause the problem. Obviously, DO NOT TRY THIS IF YOU DON'T KNOW HOW TO AVOID ELECTRICUTION - sets hold a pretty stiff charge even after unplugging them, and can really hurt if you get zapped.