Just in case it's useful, my SurfaceBook 2 stopped charging which was always done via the Surface Dock. I have no idea why this might be, but flashing the firmware (on the Surface Dock) to the latest version resolved the issue and it started charging again.
HOWEVER, a side-effect is that any USB headset that is connected whist the laptop is docked with have intermittent microphone issues. Actual sound playback is fine.
Hi Ian,
How did you manage to update the firmware of the Surface Book Base?