I have a Sony IS10 home theater system, it's worked great for 2 years. Just the other day, the sound went away. I turned the system off, waited a few minutes and turned back on. When it came on, so did the sound but, for only 10 seconds. Then it faded away. I checked all the cables and all are fine. I've turned it off for a day, turned it back on and the same thing happens. Any suggestions or advice? Thanks in advance.