In the mean time i have returned the monitor to the store i purchased it from.
They told me the Backlight bleeding was considerd to be defect and so i returned to monitor and let them refund it (i don't feel like going into the whole RMA buisnes, and in my experiance the problem won't be solved with a simple repair).
Besides the Back light bleeding i also noticed the monitor sufferd from quite some IPS glow, i know it's part of IPS technology but this is the worst i have ever seen! I own more then 4 IPS monitors they cost around 200,- euro's this one BY FAR sufferd the most from IPS glow and that for a premium monitor with a premium price!
Before i returned the monitor i also contact Asus support, and i recieved a dis concerning e-mail back regarding this isseu!
"Of course not, ASUS has higher quality control standards than other competitors. Since the beginning of December 2015, we’ve took additional measures to further tighten our quality control for the PG348Q . As mentioned before, with the current IPS technology for high specification panels, it’s not possible to have a panel completely free of any backlight bleeding. In addition, each person will have a different tolerance of what is acceptable and what is not, so therefore the backlight bleeding issue is heavily based on individual perception and will be measured and assessed differently for every person."
So they admit these monitors suffer from (in my opinion) major panel problems!
I just wanted to tell you all this for those who are considering to purchase this monitor, be aware of theses isseus!