I have reinitialized once already.
This started when our AA quit working after our people tried to change the AA greeting. We called our vendor, who said it was a bad hard drive, but wouldn't support it, and only wanted to sell a new system.
Too much of the NAM appeared to be working, that I hadn't accepted that at face value.
These are the steps I've taken so far:
1. I restored an older backup, then updated all of the mailboxes.
2. Created a new back up. We thought everything was working again, but then realized that the voice prompting wasn't there after the AA greeting.
3. I then reinitialized and restored the newer backup, but we're still at the same place.