Having issues with new Intensity Shuttle Thunderebolt

Have brand new Intensity Shuttle Thunderbolt on Macintosh. Connected VHS VCR to composite video and RCA audio jacks. Ran Desktop Video Setup and configured ports.

Run Blackmagic Media Express. The menu screen of the VCR looks fine but when I play a video I only see occasional flashes of the video.. I connect the VCR to a TV and it plays fine.

Any ideas are welcome!

Use the Search and look for VCR or TBC (Timebasecorrector) For capturing you need a stable sync signal.. And a VCR does not have a stable sync signal at all..

VHS tapes have very poor time code, and usually quite a few breaks in the TC. That is why a VHS tele,player will not directly play for a video capture card. A CRT TV was more forgiving, and would display the i ge, but not a digital system looking for the TC to sync the signal with. You need to get an old used Broadcast TBC (time vase corrector) that can rebuild thr TC and allow for a capture. See Live Production Forum and do a search for VHS and TBC for details.
Cheers

... also I have to acquire from mini DV, ilk live key gives me this message:
Blackmagic LiveKey is not supported on this DeckLink model.
do I have to update the drivers?
and if so, just trash the icons to uninstall the old ones?
please help me, go from pc to Mac, it's difficult!

You don't need Livekey for capturing.. Livekey is an application that can be used on Decklink cards to KEY a image over the SDI video and loop out with keyed image on it..
Desktop video and Media Express is what you need.