GigPerformer + Inner Pitch Free + VST2|VST3 + Windows => high CPU load on stop when after another plugin

Repro can't be with only Inner Pitch, it needs another plugin before eg: ValhallaRoom VST, Vocal Menace VST, BYOD, AIDA-X VST, Mayerism VST...

> All behave exactly the same (High CPU usage while idle and low CPU usage while audio is going through the plugin). ValhallaRoom is interesting. You need to wait for the Reverb tail to end (which takes a little longer) and when it ends CPU jumps to higher values when it stops. Very weird indeed.

Which is a textbook description of denormals, now it's a wonder which callback contaminates the control word... because under VST2 I don't think we can even have such a faulty callback.

Reproduce the issue with Inner Pitch after one of the listed plugins, then compare idle and post-tail CPU behavior under VST2 and VST3. Start by tracing the relevant audio callbacks and control-word handling; done means CPU usage remains normal after processing stops.

Written by the indexing model from the issue text.