As I expected …
What I am looking for is a problem where you get occasional bangs on DSPA, and not with the same preset on DSPB. This is usually a sign of bad delay memory. If this happens, you can get a click from reading the bad memory, which is of course hugely amplified by the effect of the reverb itself. It happens on DSPA rather than DSPB because the demands placed on DSPA are greater.
If we think this is the case, we can run some tests to confirm before you would have to send it anywhere.
