I think that your problem is down to using a mono bass – you should get a stereo one. Ho-ho.

The Bank 66 presets mix inputs left and right inputs and produce a stereo output. If these work, it means that your output connections are fine – the problem must be the input. Look at the input led meters and you will see (I think) that only one column is active, showing that you only have a single channel (mono) input. This would explain your problem.

If this proves to be the case, you can fix it by either persuading your poreamp arrangement to produce a stereo output, or by changing the routing so that analog 1 feeds both dsp inputs.