Arobat Reader shows hyroglyphic / weired characters

Since weeks we have the problem, that most - not all - PDF openend with Adobe Acrobat Reader 24.002.20857 shows hyroglyphic characters. Any other PDF viewer shows the PDF correct. Any other user on the same machine can open the PDF with Acrobat Reader without any problems, only one specific user is affected.

What we tried so far:

• We created a new user profle. That solved the problem for a few days, than same symptom.
• Uninstalled and reinstallt Reader -> no solution, problem persists.
• Used the removal tool and some handcraft to delete all traces of Adobe, reinstalled Reader -> works for a few days, than same symptom.
• Just today, un- and reinstall didn't help. Again with the removal tool and some handwork, reinstallations -> now it works again. But surely again only for a few days.

We found no traces in the eventlog or any other logs. Windows 10 22H2 is patched.  The user has no admin rights, we can't see that any kind of software or patch is been installed around the time when the problem strikes again.

Dr. Google shows some similar posts but most of them without answer. When there was a answer, we tried the solution but with no permanent success.

Any hint is highly appreciated, many thanks in advance!