Ok, looks like I made that Swell feature occur using a peak detecting envelope to trigger an ADSR. The ADSR amplitude modulates the incoming signal before the multitap delay. I wanted predictable Rise (attack) time, hence the use of the ADSR. Problem is, I think I tuned this ADSR primarily for the use case of a bunch of taps stacked up, so the sustain and release times are quite short (100 ms). This is the "gating" sound you are hearing. The audio falls below the trigger threshold and the sustain / release portion is engaged. I honestly didn't think of your particular use case. I agree it would be a nice addition.
Here's the rub, if I just go in and increase those times, I'll probably be messing with lots of peoples' presets when they update. Perhaps I could tweak it such that at small numbers of Taps we tie the sustain/release to the rise time or sensitivity? This would break fewer presets I imagine, but still a significant change…. hmmm… maybe if enough people ask for it, this would be acceptable.
