Last night my wife was on the phone when all of the sudden the phone started giving her a fast busy signal. She brought the phone to me and asked me about it and I told her I didn't know what it was. Unfortunately I wasn't in the room where the RG is and before I could tell her to not hang up and try again, she did. It worked fine after that but  I was wondering if:

A: This has happened to anyone else?

B: What it is/was?

C: Is there any type of log on the RG that might tell me if the service dropped or not?