Thank you for your answer. Wich codecs should I download? I do believe i have the latest version of final cut pro x.
At this moment my main problem is that I have to edit a xvid avi file and it has to be done tomorrow. Wich other codec can i convert the xvid avi file to that can be easily edited in FCPx? I’ve read that the most succesfull way is to convert to prores 422 so either I will have to find a way to let MPEG streamclip convert to prores 422 or use another codec available.