How to hard reset the VoCore2 Ultimate?

As explained on the manufacturer's site, you can connect to it's console via USB:

VoCore2 Ultimate, VoCore2 Audio have on board USB2TTL, you can directly connect its microUSB and your computer.

They provide a link to a YouTube video tutorial.

Basically:

• Plug it in via USB.
• Install the driver (Windows 10 may do it automatically, but otherwise the manufacturer provides drivers for various OSs on their site).
• Fire up a terminal program (PuTTY should work).
• Set it up for a Serial connection of "115200bps, 8 data bits, no even-odd check, 1 stop bit".
• Connect to device.

You should now have console access so you can reset the networking (etc.).