I picked up one of these bass effects pedal used, a while back. I only recently decided to plug it in to my laptop via USB. It works, so I thought I would document that somewhere.
It shows up as a “Texas Instruments PCM2904 Audio Codec”. It works like a 2x2 audio interface (although the only input is a single instrument input) with zero latency monitoring. In other words, I hear Ardour’s main out in the headphones plugged into the B2.1u’s output. I hear my bass’s signal mixed in, and have to tell Ardour not to do monitoring otherwise I get a delayed copy of my signal mixed in as well. It will send the dry signal while bypassed, and the wet signal when not, so you can “print” the unit’s effects.
The only tweak I had to make was to my laptop, a Lenovo X1 with CentOS 7. I used tuned-adm to set the profile to “latency-performance”. That made it record click- and pop-free at 1024 frames, 2 periods, 44.1kHz.