I just connected my Macbook via USBC-->USB cable to my Nexus 6 "TurboCharger", which charges the Nexus in less than an hour. The Macbook says "Not Charging" and the percentage isn't increasing. It's not decreasing either. When I do the same with the 2A charger from my car's 12 V outlet, the Macbook charges just fine, and pretty quickly (I'd say ~1 hour to charge it fully). Yet the same outlet doesn't charge my Nexus 6 as quickly as the supplied TurboCharger does. What's going on here?