Help! Control Room Stereo/Mono Toggle button blank

Hi, I upgraded my workstation and reinstalled Cubase 8.5 Pro on my new workstation. Now Cubase doesn’t have an option to toggle between stereo and mono in my control room. It is just a blank button where as before it would toggle from stereo to mono. Please Help. I have attached a photo.

Hi,

Could you send a screenshot of your VST Connections > Studio, please?

Sure, heres a screenshot.

Further up the tab is a section called downmix presets…Open this and then try Alt clicking on one of the little down arrows reset them to defaults which should be 1 stereo 1 mono.

Thanks! That helped me solve a problem I have been trying to fix that past few days!