I am having a similar problem.

This morning my display clock stopped for approximately 20 minutes. Then it resumed where it left off, effectively making it 20 minutes late. The actions that led up to this behavior:

1. Start car. Previous playlist resumes playing.
2. Switch to another playlist after 5 minutes.
3. Look down a few minutes later and notice that the clock has stopped on the Info screen.
4. Continue drive. Clock resumes operation after ~25 minutes.