Okay, I bought myself a 400+ a while back and I'm having some weird issues with EQing the thing. First of all, I am getting a good tone that I like, and I'm pleased with the amp, there are just some things I don't understand. Also, I tend to not use the graphic EQ, though it seems to be working as I would expect. I have read through the user manual and understand how most of these eq knobs are supposed to work and how they work together. Some things that don't work as I would expect: Unless I pull the treble knob, the amp has zero low frequency, no matter the rest of the settings, no matter the cabinet I have it hooked to. Knob in = thin, weak, no-punch sound. Knob out=sudden boost in bass frequencies. Also, the treble knob is way more powerful and sensitive in tone-shaping than any other. The mid knob doesn't seem to do anything. I can sweep it up and down 100% and nothing happens. This is true regardless of the where the rest of the knob are set. Anybody with 400+ experience ever run into anything like this? Perhaps I just don't know what I'm doing, or does it sound like my amp may have a problem? Thanks for reading, and thanks for any help.