BMD Intensity Shuttle issue with 10.1 anyone have similar

Just wanted to check if anyone is having issues using a BMD intensity shuttle for AV output via Thunderbolt with 10.1..
I have an iMac latest running Mavericks and suddenly for no reason I have lost picture output to the TV monitor. It was working fine all morning I left the project up and went to lunch, when I returned the TV monitor was black and there was no audio, when I checked the BMD app in prefs it was greyed out??? so I reinstalled the BMD software and it worked for an hour then just disappeared again however the Audio is still good.. If I go to System Pref and change the settings in the Black magic app the new frame rate will appear on the screen as per normal but FCPX will not output a picture just a black screen..
I have opened FCP7 and all works perfect so there is no issue with cables etc, it must be a software issue of some kind.. I have re installed the BMD software several times but no luck..
I trashed the FCPX prefs, no luck so re installed
FCPX just to be safe, also no luck.....
Can anyone can give give me an idea of where to start that would appreciated as this one is doing my head in.

Sorry if this is long winded, brain is a bit fried trying to sort this one..

Cheers
Truestory

I'd recommend immediately contacting BMD support.