When opening a project from C6.5 into C7 then playing with a midi track with VST instrument and a keyboard, I get latence with my keyboard.
If I start an new project in C7, creating a midi track with a VST instrument and using my keyboard, I get no latence.
Look at your asio buffer settings, your project contains asio settings so it could be possible that with the c6.5 project file the latency is set different then the default in C7.
Apparently there’s a problem with opening old projects in C7 - another member reported similar latency issues.
The workaround, as of now, is to do as emotive suggested above. Hopefully this will be fixed soon.