This blog post may be useful,
The Curious Case of Quicktime Autoplay in Safari.
Ever since I installed Snow Leopard, I’ve been battling with a strange bug in Safari. If I go to a website with several embedded videos, they all start playing simultaneously. I’d been in the head of the page with no video present in the current view when suddenly all the audio streams start playing and overlapping each other.
I’ve been searching Google, combing the Apple discussion boards with no clue or direction on how to fix this bug. Then this morning I had an idea. I thought it must be a Safari plugin… and it was. I’ve been using a flash blocker called ClickToFlash and it was the culprit. When it intercepts YouTube videos it sets them all to Autoplay and they all start playing.
Thankfully, it’s been reported as a bug in the ClickToFlash support board.
there is a support ticket to fix the autoplay bug in ClickToFlash 1.5fc2
and there is now a workaround as well.
You can get the ClickToFlash settings at that post.
There is also this Apple thread discussing how to Turn of Quicktime AutoPlay
which refers to that post.
Besides my comment to yours, there is this QuickTime HTML Scripting reference that might interest you.
Appears that if the '
AUTOPLAY' attribute is set to '
true' while embedding Quicktime content,
it cannot be disabled. Though, I think there should be a way to get by that...