@ddf you seem to use vvvv mainloop nodes to modify audio parameters. since the mainloop, even if it runs at 60fps is way to slow for audio manipulation you hear all the steps as crackles. especially for fast moving motion. if steps get too big you introduce little impulses in the audio signal and that are those crackles. at least it sounds like that in the video.
some values even only update per audio buffer, so if you increase the buffer size some values will even update slower. so try a buffer size of 256 - 1024. smaller is better of course.
so go into the node browser, type 'VAudio' and try to only use the nodes showing up. especially for ADSR and other signal modulation.