Download QT 7.4.5 again and see if it makes any difference to the playback on the apple site.
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I have a Macbook, 2.16GHz Intel with OS X 10.4.11, Safari 3.0.4, and Quicktime 7.4.5.
I cannot view Quicktime videos properly in Safari. It seems to just be on Apple websites, as far as I can tell.
For example, on http://www.apple.com/getamac/ads/, when I load the video "Sad Song", it plays, but the picture's jumpy, and the loading icon flashes up briefly, every few seconds. And, when I click on the next video, "Pep Rally", the Quicktime logo appears in the video window, with the standard rotating circle icon for loading, but the audio starts to play and the icon stays in the window as if it's still loading. The audio is a bit jumpy, too. This is the same for the other videos on the page.
Also, on the movie release trailers on the apple site like http://www.apple.com/trailers/newline/journeytothecenteroftheearth/trailer4/, a control bar appears in the middle of where the video box should be and the audio plays normally, but there is no picture whatsoever. Just what I think is a quicktime control bar.
Youtube, CNET and other videos that I have been on look fine.
It's probably something to do with the Quicktime plug-in, but I don't know what I'm doing with that.
I hope someone can help solve my problem.

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