B4R Question Arduino 101 BLE strange behaviour 12v vs USB

My arduino 101 will connect with BLE when using power from USB, but won't connect using the 12v barrel jack for power.

I've tried the USB power using a wall wart power, BLE connects.

Also it's not freezing on Serial Connect because I've set up a blink to test this. Also removed the serial.initialize.

Any ideas? Maybe I need to run the board with USB power instead of the 12v jack!!