Laying off or Capturing SD/HD video, a horizontal shift occurs

So we're using FCP 7 and a problem has gotten progressively worse. When capturing HD/SD content or laying off to tape the video shifts down around 5-8 lines. Can't find anything about it anywhere. Would certainly appreciate any insight on this. Thanks!

More info needed. What's your I/O? From what machine? In the old SD days of Betacam vertical shifting was caused by not having sync going to the deck when recording FWIW. (Although it gets a little more complicated than that depending on the setup).

I appreciate your readiness to help anickt.

Capturing from a Sony SRW-5500 deck via SDI. Its on a router, which we have had work done on recently so maybe thats the culprit. If I am capturing from the deck I route house black in to it just to eliminate any extra noise and set the reference to Video In on the AJA LHi card. If I am laying off, I put the deck in free run.

What is odd is that sometimes just restarting the Mac will take care of it. I just don't get it.