Panning not working

I just reinstalled Cubase Artist 7.5 onto a new PC and now the pan settings in all my projects is not working. I’ve checked multiple projects and even channels that are panned full L or R play in both channels. Any ideas?

When you say “play in both channels”, do you mean that the output meter on the transport bar shows this, or that you’re hearing it in both channels, despite it appearing OK (i.e. panning OK in the meters)?

Maybe you should take a look in the master section at the plugins