I have a brand new spider jam, purchased just a few weeks ago. Almost immediately there has been this intermittent problem. In the middle of playing, suddenly the volume cuts down to maybe half or less. The amp was never even touched when this occurs. Once this has happened, you cannot get the volume up again. Even turning the channel and master volume all the way up barely increased the volume at all. I have found that the only fix is to turn the amp off, wait a couple of seconds, then turn it back on. It then works just fine again- until the next time it happens. It could go for hours, or just a few minutes, there is no regularity nor does the problem correspond to anything. Just here and there intermittently. It is a major problem because now I can never perform with it as it could cut out at any moment on stage. Any ideas of what could be causing it and what to do about it?