Heh, I found a recent recording of that car's door chime:
http://www.youtube.com/watch?v=WMkBhQM_Qpw
Amazing that almost six years after the old chime was retired, there are *still* cars out there that have the old chime. I will almost guarantee you that it's the case that this car was simply never changed. I don't know what the process of changing chimes entails, but obviously they missed that pair.
As I understand it, they got all of the Rohrs and the non-rehabbed Bredas entirely, because once the new announcement started being deployed, I never heard the original version of the Sandy Carroll announcement again. The 5000-Series apparently took a while to do, since obviously, they *still* haven't gotten all of the old recordings.
The 2000 and 3000-Series Bredas were all delivered from Alstom with the second version of the Sandy Carroll door announcement and chime following their rehabilitation, even after the door announcement change. Thus even after the new announcement was official, they still came back with the old announcement and then had to be changed by WMATA. Same with the 6000-Series, as I understand it. Those were also delivered with the old chime and changed after they got back to Metro.