Problems with PT Quartet and PT project sample rate

Hallo PT community!



I've recently bought a PT Quartet and today I tried to open PT sessions I created with my old interface (MBox 3 normal).



The thing is that when I open these sessions, PT claims that:



"The current playback engine does not support a sample rate of 48kHz."



I then set my Quartet, from the PT IO Control Panel, to 48kHz and try to open the very same session again. To my surprise PT this time states:



"The current playback engine does not support a sample rate of 44.1kHz."



Is there any known incompatibility with old PT sessions created with other interfaces and PT Quartet?



I am afraid not being able to retrieve my older work.



Any help or insights will be very welcome.



Thanks for your patience,



Nil