zabukowski wrote:Finally, I've found the cause for this misbehavior:
Moving processReplacing call to the main "audio callback" function of my host solves mentioned problems. Previously it was called from a separate, synchronized thread.
Looks like processing call not being 100% bound to audio interrupt is causing anomalies with GUI of these plugins.
That sounds pretty weird, considering most hosts these days will process on multiple cores, which implies processing in multiple threads. Maybe there's some problem with your threads .. especially on Windows you have a dozen ways to create threads, and the "correct" one is almost certainly _beginthreadex (maybe _beginthread works too, can't remember) and while some code (especially simple DSP code) might not care, the other options can skip CRT init or such (specifically CreateThread(Ex) would be a terrible idea).