After awhile, Nuendo 11 crashes when loading Altiverb 7, doesn't crash after computer restart

Hi,
I seem to be having a weird anomaly with Nuendo 11 and mainly Altiverb 7. Using Windows 10.

After running Nuendo for a few hours, and when I try to load an instance of Altiverb 7 in a dense project, Nuendo hangs.

I’ll then have to restart the computer, and open a fresh Nuendo, load Altiverb, and this time, it doesn’t hang.

But again, after a few hours, when I try the same thing, Nuendo hangs. Tends to happen with Cubase with certain plugins as well.

Any ideas would be much appreciated. Thanks.