It's probably about the Web sites and how well they're programmed and whether they're programmed to go along with your browser. It's like the old days when we had different HTML standards, Netscape and Windows competing and you could see some pages great with one and not the other, etc.

Now though it's the competition of the browsers and media files and not all site creators honor all browsers or they use a media file your computer doesn't like, etc. I use Google Chrome and my credit card people didn't like that the first time I tried it, maybe eight months ago but I think they do now. Notice the sites where it works or doesn't with your browser and use a different browser to see if it works with that one? But it could be the media file the streaming is done in.

Here's a how to make it that might explain what's going on so you can see if you can understand what you have and what might be going wrong: http://www.mediacollege.com/video/st.../overview.html