I have a new 2016 MBP and could feel a tingle from the metal frame when charging, but not when running on battery. Curious, I put a digital multimeter on the USB C cable. The shield (the metal shell on the exterior of the plug) shows 35 to 50 Volts AC to ground when the power adapter is plugged in using the supplied duck bill plug! When I attach an old grounded plug adapter from my previous MBP to the power adapter, instead of the two prong duck bill plug, it goes to zero (as one might expect) and there is no tingle from the metal frame of the MBP while charging. I assumed it was a defective power adapter and got a new one from Apple, but it has the same issues. I have read in older threads about previous MBPs that others have claimed this is common when using an ungrounded plug, but I have never experienced it before on any previous MBP that I have owned. I have not seen any reference to this issue with the new MBP. Has anyone else noticed this? Does anyone have a digital multimeter they can use to check their USB C plug? If so, do you have AC voltage on the shield of the USB C cable while plugged into the power adapter? I suppose this is not a huge deal, but it seems odd (and potentially unsafe) to have that much AC voltage leaking through the power adapter to the USB C cable shell. Thoughts? Comments? Thanks for any help or insights anyone can offer!