Capture device offline... or loud buzz noise

Hi,

I am trying to use the same cam (Canon HV80) - miniDV tapes on a 1394 Firewire under Mac OS X Lion 10.7.4, Adobe Premiere CS6.

On the usual FW card (I have 2...) - by usual, I mean the one I use when this PC is booted under Windows 8, with Premiere CS4 - where everything work fine, but when this macine is booted into Mac OS X, I get ''capture device offline'' message. So I tried the other card (a SiiG with TI chipset), as soon as I open the ''Capture screen'' in Premiere, I get a loud noizy buzz from the camera...

Thanks for any help,

Rob