Blurry graphics

Good morning,
I use your program a lot to convert Excel graphs to PDF via a macro. In recent years, however, the graphs have all become blurry for me. The only solution is to do them one by one (and there are many).
I don't understand why this change.
I tried with various profiles, but nothing.
I wanted to buy the "professional" one, do you think things can change?
Do you have any advice for graphic designers?
Thanks
Dilly