Cremona Strings - Strange Vibrato/Tempo Issue

I'm using Cremona Strings with FL Studio. FL did just have an update, but this issue only seems to happen with Cremona and it seems pretty specific. I've also tried a previous version of FL and I seem to be getting the same issue.

I'm on Windows and my copy of Kontakt (as well as the strings) are up to date according to Native Access.

If I play the Amati Viola in Virtuoso at a tempo of anywhere below 150, it's fine. If I play it at 187 or above, it's also fine. Anything between 150 and 186 and there's this static/crunch/popping that occurs which sounds awful.

If I lower the expression down to zero but leave the vibrato alone, you get just the popping. Changing the vibrato style doesn't seem to do anything, nor does moving down to "Sin" or reducing the rate.

Similar issues occur on all of the Cremona Quartet instruments. They sound gorgeous outside of that tempo range (higher or lower) but within it, it's a bit of a nightmare.

I've tried closing and re-opening FL, restarting my machine, updating Kontakt, and changing the audio source, but if I'm in that range it's just bad news.

Thanks for any help or insight.