Firebox Presonus [discontinued] - Only 1 track recording

Hi,
Looking for some advice on setting up the Presonus firebox with Cubase 8 on Windows 10 connected via firewire.

The Presonus has been updated using 64 bit drivers and has been working on Windows 10. Recently the Presonus has not been able to record multiple tracks from multiple inputs [midi, guitar, bass etc]. This was working before.

All 6 inputs are set to mono in the VST Connections. All Device ports are set to the correct ports [I believe]
The VST outputs are set to Stereo Out, and device ports are MainOut 1L/1R. Adding more ports doesn’t seem to make a difference. Can’t hear anything on other tracks even though Cubase seems to pick up audio [meters showing audio] on other tracks. Recording won’t work, it only records a blank track in Cubase.
The first mono track in VST Inputs is the only port that seems to send audio into Cubase that can be heard in Windows. If that port is changed to other ports, the audio comes through.

How can I get all multiple inputs in Cubase through the Firebox? What settings need to be changed?

Thanks.