The IPlugEffect's UI frequency is 15 Hz. How to change it?

My IPlugEffect.exe is slow because the time interval between OnMouseDrag() events is 64 ms (I measured it myself by means of a C++ code). 64 ms corresponds to approximately 15 Hz.

The VST2 variant of the same plug-in works much faster in Reaper and FL Studio: the time interval between OnMouseDrag() events is 8 ms. It corresponds to the frequency of my Logitech M90 mouse (125 Hz).

I wish to get a similar frequency in IPlugEffect.exe (or in IPlugEffect.vst with my simple host).

Changing PLUG_FPS 60 (in config.h) by any other value doesn’t help: the real frequency is 15 Hz even if I set PLUG_FPS to 4 Hz.

I tried to run the same IPlugEffect.vst by means of “minihost” from Steinberg’s SDK - the measured frequency is 15 Hz. In other words the same VST2 plug-in gives 125 Hz in Reaper and 15 Hz in minihost. What kind of magic is this?

I tried to run effect->dispatcher(effect, effEditIdle, 0, 0, 0, 0) in my host with the frequency of 60 Hz - the measured frequency remains the same - 15 Hz. It looks like the plug-in simply ignores the effEditIdle messages.

I use IGRAPHICS_SKIA;IGRAPHICS_CPU; Other variants don’t work reliably on my computers.

If anyone can suggest an idea on how to change the frequency, I would be very grateful.