I decided to use the amp with headphones. The sound is very overdriven, and am not sure why. Even at low volume, gain, and master levels. Anybody have any suggestion of what the problem may be, or have encountered this? Through a cab it performs normally and I've never had an issue. The headphones are cans that, while not expensive, work fine for other applications like the vox headphone amp that plugs straight into my bass jack. Any ideas? Thanks in advance.