Onlyoffice spell checker eating 50% cpu resources

fresh install of Ubuntu server 20.04, nextcloud manually installed (LAMP, Nextcloud, Lets encrypt, Onlyoffice server)

I was able to setup the Onlyoffice server and it looks like the spell checker is having issues eating resources in the background. Here is a screenshot of the system resources with the spellchecker stopped:

Here is what happens when the service is started:

The onlyoffice spellchecker and other modules start eating up cpu right away.
I followed this guide to reinstall the spellchecker service:

Actually, the spellcheck does not even work on the online docs:

Yes it is enabled in the advanced options.
Any ideas?
Thank you