Hi Dan. My Q3 had a hardware/software problem maintaining connection to the LTE Audi network and would annoyingly reset the whole MMI at low signal levels. It would lose everything, Radio, phones, Sat Nav for about 10 minutes. Just dead. Usually as I was about to cross the QE2 bridge over the Thames into Kent. No Sat Nav is just what you want when entering one of the busiest parts of the M25! It was solved by replacing the car's MMI computer and latest software ... under warranty of course. But they wouldn't tell me further details.
The q2 problem, very similar to this one, was solved by a lot of my time talking to, and performing tests for, Audi Connect Support in Germany who produced a Software update for my dealer to install. Worked fine after that. Again no further details.