I recent bought a tascam DP-01, an 8 track DAW. When I plug my bass in, either directly to the unit thru the "guitar/bass" input, or into the mic input via a direct box, the bass is barely audible with the line gain knob 1/2 way up. I turn line gain up to 75%, at this level the volume is barely okay but there is a lot of noise. All levels on the assigned track, master volume control, and the bass itself are set appropriately, it seems. Do the mic preamps just really suck, or is the unit defective? Support at tascam.com is not too helpful. Any insights would be much appreciated.