Hi,
I have the same basic setup. My system has been rock solid since day one 2 1/2 years running.
My SP card is in Slot 3.
In your post you state that all of your hardware came from apple except the decklink card.
What are using for video storage? Do you have an external raid? If you are using the internal drive
for digitizing you are asking for problems from the get go.
As far as moving cables and such that would sound like some kind of hardware problem.
The guys from Blackmagic are fantastic on helping resolve problems be it software or hardware problems.
Don’t throw in the towel yet on Decklink. I feel your pain on trying to finish projects for clients and your system
is throwing you under the bus!
Good Luck!
Brandon Tyler
Tyler Productions
G5 Dual 2.0, 1.5Gig ram, Atto UL4D, HUGE Dual 320 1.2TB, Decklink HD/SP, Quicktime 6.5, FCP HD