Pocketbook lux 5 VCOM settings

Hi all!

I was wondering if anyone knows whether it is possible to change the VCOM settings of the lux 5 (PB628).

I replaced the screen of my broken lux 5, and it works but with a lot of ghosting. My guess is that the VCOM is different from the original, but I can't seem to find out where these settings could be changed.

Thanks!