After upgrading from 4.2 to 4.51 I no longer get an audio or video signal to my external monitor from my Raptor RT card. I haven't changed any settings and cannot find any info in the application settings that refers to an external monitor. It seems that all other features of my dual monitors are working fine.
( Just did some deeper digging through the posts and found my answer) It seems that my project settings defaulted to my OCHI card and of course wasn't sending a signal out through my Raptor card.