LO stops responding on keyboard input, windows 10

I have a fresh install of windows 10 on a new laptop with lots of memory and resources.
This is a system with RTL bidirectional typing (Hebrew).
Running nothing but LO Writer, if I just bang the keyboard after a few characters it hangs, recovering after a few seconds. This continues all the time, every few characters it hangs. It hangs worse in Hebrew than in English.
I tried disabling OpenGL (Options - View), no change.
Windows wordpad works smooth as expected.
Downgraded to 5.1.6 and turned off spellcheck and it is almost smooth.