Gizmo_A6

I'm new around this forum and to Audi but I have an annoying issue with my MMi...

The seller of the car told me that it rebooted itself every 5 or so minutes....figured it might be an easy fix but thinking I should have done my homework beforehand....hindsight

So, it does reboot every 5 or so minutes, sometimes longer, sometimes shorter....I have noticed one of the buttons by the rotary **** is very stiff to push so thinking it might be liquid damaged BUT when I press NAV or INFO it sits at "Initialising Navigation" and never goes any further. I've taken the disk out of the NAV and it recognises no disk but it just wont do anymore.

I need to get hold of VCDS or VAG COM but funds arent in my favour at the moment, wondered if anyone had any ideas to get me started in the journey of fault finding!