Fedora 17 Youtube Slow

I have just installed Fedora 17 on my Netbook Acer Aspire 750h. When playing Youtube for the first time it says missing plugin.I then chose the download and install of the Adobe flash player.

I can then play Youtube after restarting the Firefox browser.

However, when playing the Youtube it seems slow.

I googled and found that there's a lot of complain about Youtube and Adobe flash player. What should I do to resolve this ?

Please help.

Thanks.
Cheers
David