Using Cubase 6.0.5 on Mac OS 10.6.8. When I try to do File->Import to pull in an H.264 video, those vids are greyed out. YET, if I have a project that is referencing a MOV file, and I delete that MOV and load the project, and it asks me to locate the vid, I can point it to an M4V file and it works perfectly!
Makes no sense why Steinberg decided to restrict M4V files on import. Clearly they work fine, actually better than other formats. Other video formats cause me problems, like the playhead stops moving during playback, then Cubase eventually starts locking up on me. H.264 format is perfectly smooth.