VSTs locking up the project

I was getting some glitch skipping on a project with a good number of VSTs. It would export the mix ok, so I’ve been tolerating the momentary playback rips. Then I thought I should address it. In Studio Set Up, I saw in the Advanced Section, the Processing Precision was 32 bit Float. I thought maybe that should be 64. My operating system processor is x64. (G4G memory) Activate Multi-Processing was checked, so it should be using all of the 16 cores. In the Yamaha ASIO driver I increased the buffer from 384 to 768 samples. Then, the project grinds slowly to a halt. I reset everything and it still rips and tempo drops to a crawl. A prior saved version rips but does not stop. Other projects ok. I suppose I can and was mixing down the VSTs to audio. Any ideas? Besides external accelerator $$? If so, which one?

Hi,

Set the Processing Precision back to 32 bit Float.