Then, 3b-a. Uninstalling rewind to see whether it helps.
I remember to have had similar things on Windows+Firefox. No matter what website, no video. It plays, but black. It was like it was overlayed with something, because going full screen and back fast, or start/stopping it fast, somehow helped for this one view. Also while going full screen and back, I could see some parts of the video flashing on the sides..Next view, may be - may be not - black.
There, switching off hardware acceleration helped, too. Until it started to show the same behavior after a short period of working, too. Then switching it on again helped. Also, switching off and switching on while video played.
I think, then I switched off the settings flag to use some specific codec (like "always use .264" = off ) in my browsers settings. The problem went away after some system updates or some codec installations.
... May be there's a codec pack for Macs?
Your next steps could be:
- 3b-a (if each drm video has problems..)
- Try to find out if there is a possibility to switch off/on forcefully set codec in your browser. May be Netflix will serve another codec'ed files then.