It's real. I was able to replicate the regulator error. No USB connection. No other devices or shields attached.
Test Setup:
Black wire: GND
Purple Wire: Vin
Red Wire: +5V
Orange Wire: 3V3
http://www.surfruss.com/Arduino/Connections.JPG
http://www.surfruss.com/Arduino/ConnectionsCloseUp.JPG
Wall-Wart Power Supplies:
http://www.surfruss.com/Arduino/Wall_Warts.JPG
First test with the 12Vdc PS:
Vin: 14.37Vdc http://www.surfruss.com/Arduino/12V_Vin.JPG
+5V: 4.98 http://www.surfruss.com/Arduino/12V_5V.JPG
3V3: 4.16Vdc http://www.surfruss.com/Arduino/12V_3V3.JPG
Then the 9Vdc PS:
Vin: 8.38Vdc http://www.surfruss.com/Arduino/9V_Vin.JPG
+5V: 4.98Vdc http://www.surfruss.com/Arduino/9V_5V.JPG
3V3: 3.30Vdc http://www.surfruss.com/Arduino/9V_3V3.JPG
"Nothing up my sleeve, presto!"
Regards,
Ru55