Because your online videos are tightly connected to Windows Media Player, here is a little player tweak that might work. Open Windows Media Player, go to Tools, Options and access the Performance tab. Set the Video acceleration to None, hit Advanced and deselect Enable full-screen mode switch option. Hit OK, Apply and OK. The same solution can be applied directly on your online videos. Right-click on your online player, go to Settings and from Display, deselect the Enable hardware acceleration option. If none of these solutions works, go to http://k-lite-codec-pack.software.informer.com/ and download and install the latest version of K-Lite Codec Pack.