In my experience this is nearly always a sample rate issue. AFAICT, Cubasis is always recording at 44.1 since it converts things to 44.1 when you drag them from the Media Bay…can’t find anywhere to change this.
BTW, what causes something to play too slow is if it has a higher sample rate than the session…! So you probably recorded the file at 48kHz, but it is playing back in a 44.1 session. What I would do is double-click on the file to open it in the audio editor, hit “Save to Media” in the lower left hand corner, then find it in Media Bay and re-import it. If it knocks it down to 44.1 when you import it, that was the problem.
Interesting - I hadn’t thought about this since there is no ASIO/CoreAudio control panel anywhere…