Run an internet speed test, sounds like your internet maybe the problem. Also what browser are you using on the mac ? I would try Firefox for Apple Mac and install latest adobe flash player threw Firefox too as a test if you don't use Firefox currently.
Internet speed test page here.
http://www.speedtest.net/
This explains how to install Firefox for Mac
http://www.mozilla.org/en-US/firefox/video/?video=upgrade-mac
Then go to this link inside Firefox for Mac to install Adobe Flash Player.
http://get2.adobe.com/flashplayer/
Regards
Nabil
http://www.flirt4free.com/
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