Thanks for the quick response vim.
i was not planning on using the video mixing so i actually hadn't tried to play a video clip yet. Will try now...
Just put one on which worked fine and got rid of the flicker but after closing FDpro and re-opening the flicker returns!
Not a massive issue but still a bug to report.
if anyone else has this on there macbooks i'd love to know.
might add some video decoders to the osx and see if anything improves.