Found out I was doing something dumb with the ADSR envelope settings in supercollider. Namely, uh, setting the D to zero while setting the A to something nonzero and the S to something noticeably less than 1. So the envelope ramped up to 1 over a nonzero amount of time, but then abruptly dropped down to S. Fixed the problem, and now I have less clicky attacks. Also playing around with drums and filters 'nnat.
~30 seconds of improv over Ebm-Ab5-B chord progression.