Graphics problem when streaming

Hi,

In my Windows PC I have Kodi installed for more than 2 years and it was working without any problem.
Few weeks ago, I started having a problem with the image during streaming, please see picture:

[img]
https://mega.nz/#!IwRj2Zaa!wVBPNZ39n3K9j…1e-snnAm2A
/img]

Basically the right part of the screen is disturbed as if a filter is applied on the image.
This problem happens only during streaming online (e.g. from youtube) but not when I play a movie from my hard drive. The rest of the software graphics (menus) is perfect.
I unistalled and installed again Kodi but nothing changed.

Any advice to solve it?
Many thanks in advance!