Recently my volume has started to fade and the come back up. At first I thought it might be the batteries in my bass going dead so I changed them with fresh out of the box batteries. I think this is an overheating issue since the problem occurs towards the end of the evening. I'm running the amp in the bridged/mono mode into a Hartke 4x10 cab. The amp does sit in a SKB hard road case. Anyone ever have a similar problem? Solution? Ideas? Speculation?