Have tried to use this module quite a lot of times as aux/return for distortion pedals, filters, as audio input from my computer and as "pre-amp" for a spring reverb.
With destortion pedals it was very hard to supress feedback. When no audio came in, feedback swelled up horribly.
Using it with a sherman filter, it tended to color the sound too much and creating sudden resonant peaks (probably also the feedback)
While with the spring reverb, the gain was not enough to get the spring sound to a high enough level and be audible along the rest, while not being mostly amplified background noise.
Lastly, somehow the audio coming into the module bleeds through to other modules on the same rail..
Starting to think I got a damaged module..