nRF52 DK PPK Negative Current

Hi all,

first I have to admit that I'm a total rookie in "electricity". I know BLE software-side but just started to learn the hardware stuff. I just received my PPK and connected it with the nrf52DK (as explained in the infocenter). It shows a negative current (connected via Micro USB to my MacBook Pro with Touchbar). Is it my fault? Or could it be that there is a problem because the PPK software is running in Parallels? As a side note: when run in Parallels on a 4K screen the PPK software does not show the units...

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