Hi Jake,
Which specific card is this? To check, simply go into the OS X System Preferences, click on DeckLink and it should tell you the type of DeckLink card near the top of the preference pane.
What is the model of the Sony TV?
Since you’re on an SD card, the card should down convert the output to the TV if you’re working in 1080i60 or 1080i50. However, you should still use the HD easy setups in Final Cut Pro.
regards
Kristian Lam
Blackmagic Design