El Capitan video playback is not working

After upgrading to El Capitan, i can't seem to play any videos online. Youtube, Netflix, Amazon all load the video but it never starts playing...it just sits there on the first frame.

I've tried both Chrome 45 and Safari 9, and neither work. I've also uninstalled flash and silverlight, tried without them and then reinstalled both. Looking at the code, i can see the videos are playing using the HTML5 player in the browsers and not silverlight/flash, so i'm not surprised it didn't change much.

It's not a connection issue as other macs (running Mavericks) still work fine and i'm pretty sure i haven't changed anything around video for a long time. All three sources worked prior to upgrading to El Capitan