Cubase 8.5 Pro just stops playing certain VST instruments?

Hello everyone,

I just encountered this problem recently.

I added a new instrument to my project (which I have a TON of VST instruments —
(i.e. 17 VST instruments with about 8 (omnisphere) to 16 channels (spitfire audio and VSL) of instruments (about 62 gigs of sample data)).

I noticed that sometimes, after a while of playing just fine, it stops playing KeyScape and/or Omnisphere?

The strangest thing is, that if I quit the project (no small task considering how big the project is adn how much memory needs to be freed) and re-open it, everything plays fine for a while, then it seemingly randomly quits a particular VST instrument.

I searched around on the forum and many suggested increasing the buffer size. I did this but to no avail.

Any suggestions?

Thank you for ANY help you can give me,


If adjusting the audio buffer size has not made a difference then I recommend trying a different approach. Please view the following 3rd party video as it covers topics that are relevant to your issue:

It has been beneficial to all the users I have shared it with.