Can't Create More Than Four VST Connections

Hello. I am unable to create more than four mono VST Connections using Cubase SE 3.0.3, Build 658. I am using a Presonus Firestudio 2626 which has 8 inputs, all of which are accessible, but I can only create four inputs. In fact, I can create four stereo inputs with all 8 inputs, but I really want to create 8 mono inputs.

The Device Manager shows everything my Presonus 2626 has to offer, and I can even change the ports on the four mono connections to any of the above, but I cannot create more than four mono connections. I have also tried clearing everything, then selecting the ‘8 Mono’ preset, and it just puts the four back again.

Any thoughts?