I have a 10 gallon 125 PSI Brute air compressor. I have used it about 5 times since I had it. The last couple of times, I could hear a hissing sound, and it stopped as though it was loosing air. I was using it on January 18th when it stopped and has not run since. electrical connection is good,but, the compressor does not start up. Please advise what my problem might be. - Thanks