This message was posted on behalf of Intel Corporation
Thank you for contacting Intel Communities.
I am sorry to hear you are having issues with the USB connection when using the EGPU.
I am pretty sure this issue is caused because the Intel® NUC you have supports only external graphics connected through the Thunderbolt™ 3 (USB-C) port using a self-powered enclosure. You can refer to the following link for further information.
Thunderbolt™ 3/USB Type C Information.
The M.2 ports on this device support only SSDs, please check the following link for information:
Tested Peripherals for Intel® NUC Kit NUC6i7KYK.
I hope this helps.
Thanks for the information.
I've managed to get it working perfectly. All I had to do was unplug one of the HDMI cables that connect to the egpu from NUC. This setup gives you an m.2 connector with 2 HDMI cables to connect to the egpu. I figured it was too much of a performance draw to have both cables connected, and unplugging the right side cable fix the problem. Now the USB runs perfectly and VR is smooth. I haven't seen any significant performance drop. For the games I've tried I've kept the same graphics settings when I was using 2 cables and the quality and speed is still the same.
Hope this helps anyone else who stumbles across a similar problem.