Hi all, wondering if you can give any advice. I got a new iMac recently - I've upgraded it to Lion and generally speaking it seems to run OK. For some reason though, about 1 in 3 times when I try and watch a video on youtube, the imac freezes. Not just the web browser, but the whole computer becomes unresponsive. I can move the cursor around but cannot click on anything - the only thing I can do is switch the power button off. At first I thought it was just on Google Chrome but it's just crashed on Safari too. Any ideas what I can do to solve this? Thanks in advance, Luke (p.s. sorry if this is the wrong thread to post this in, wasn't sure which was the best).