Rapidcomposer playing slower than cubase in vst mode

[dark-i]

HI, yea I can't get rapidcomposer as a vsti to sync with cubase, it seems to be playing slower, as over time the notes go further out of sync the longer it plays, starts off grand and then just drifts out. I have tried this on reaper and it works fine. I have tried a lot of things in cubase but no joy. Any help would be great
Cheers
D