Unknown Name, Unknown Number

I send all anonymous and unknown numbers to VM.
How did my phone pick up "Unknown Name, Unknown Number"? 1:59PM today EST.

The first call in Call History was 13:45. (1:45) CID/CNAM got that.
Followed by 15:12. (3:12PM)

Very strange.
15:12, 15:19, 15:20, 15:22, 15:21, 15:21, 15:22, 15:22, 15:23, 15:24 all 3-5 seconds in length from the same calling number.
The only one of these was 15:24 and CID/CNAM got that.

Its like the system hiccuped over 12 seconds of a single call!

Maybe the DB was having some intense thing going on?
I guess the phone really only rang three times.