Capturing issue with Premiere

Hi,
I have a Mac with Adobe Premiere CS6 and Decklink Extreme HD. When I'm capturing analog video by Premiere, in DV or DVCPRO format, sometimes the capturing freezes (the video on premiere windows remain still). And if I stop the capturing, the commands in Premiere don't respond and I cannot save the work. Do you have some suggestion?

I have also a pc with windows 7 and Decklink extreme 3D. Same issue. Sometimes, the capturing freezes, expecially if I do some operations with the os (eg. open file explorer or so...)

I noted that, on Mac, the os continue to write the file ( .mov) until I stop the recording (clicking STOP button on premiere, even if it doesn't respond, the recording stops anyway, even if the popup window on which I can choose the name of the captured video doesn't appear), but the created .MOV file is unreadable.

Any help?

Thanks