1. Try going to your adobe flashplayer's settings manager here:
http://www.macromedia.com/support/documentation/en/flashplayer/help/settings_manager.html
Clear out sites under Global Storage Settings Panel -> Website Sotrage Panel.
2. Try increasing your Local Storage Settings for YouTube by
You may want to change your local storage settings if, for example, you want to allot more space for information from this website. To display the Local Storage Settings panel:
A.Right-click (Windows) or Control-click (Macintosh) the application image (the Video) while it is running.
B.From the context menu, select Settings, and then click the Local Storage tab.
I know in the past I had issues with flash player getting slow or acting quirky over time. Had to go through a complet removal, cleaner, and reinstall. Not sure why over-time it does that.
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If you're into experimenting you could try Firefox+GreaseMonkey and the following to see if it's really a buffering issue.
http://lifehacker.com/5120654/youtube-buffer-video-prevents-auto+playing
Your signature has been erased by a mod please reduce it to 600 x 120.
