That seems characteristic of a memory reclamation automatic garbage collection stall. The system has to keep allocating free/unused memory to hold new incoming data (audio and map) eventually reaching the point where no more known free memory is available for use allocation. At that point any task requiring a new memory allocation is stalled until the memory garbage collector finds enough allocated-but-guaranteed-not-used-by-any-task memory to return to the free to reuse memory pool for allocating to the stalled task(s) needing unused memory.

As best as I can determine, Android Auto utilizes a Java automatic garbage collection system. How well that works in a real time system like the multimedia system without garbage collection stalls depends upon the software implementation.

If your Lexus Android Auto problem is indeed a head unit Android Auto implementation memory handling garbage collection issue, the only real fix is a head unit software/firmware and/or hardware update.

(To the best of my knowledge, the Apple CarPlay system doesn't anything like a Java automatic garbage collection system for memory management. While there's no guarantee CarPlay won't ever have some sort of memory handling issue, at least CarPlay doesn't have to handle the implementation issues inherent with using a Java type automatic garbage collection system.)

 

Makes sense. Thanks.
What annoys me is it works on other cars.. So a firmware update (provided it has the fix) can fix the issue.
When they did my nav update, it only updated the map version which is only Tomcat map. So it wasn't the firmware update.
How do I know there is a newer firmware version?