DBQueue processing becomes stuck with no new jobs added after AAD-K-UserInGroup jobs get inserted into the queue.
Restarting the SQL server agent is required to progress processing of the DB queue.
The AAD-K-UserInGroup task uses the function "AAD_FGIUserInGroupValid".
This function is known to caused performance issues and blocks the whole DBQueue processing.
The modules AAD and ADS are quite similar and previously share this function. For the case in ADS, Development had optimized the algorithm to calculate group membership.
However Development has not optimized the algorithm for AAD yet and hence the DBQueue processing is observed when AAD-K-UserInGroup jobs are inserted in the queue.