Well it started with Karmic. After I updated things seemed fine but then it was weird when I would go to a site with a flash video clicking on the video would do nothing. At first I thought it must be Arora, my preferred browser these days, but that was not to be the case. It was happening in Firefox too. I started looking around and found this thread of the Ubuntu and this bug in Launchpad. The bug seemed to indicate that the problem was with Compiz but as I am cnot using Gnome or Compiz, I use Fluxbox, I don’t think that is the issues. More people started posting that they were not using Compiz either. Speculation had it that it might be something to do with nsplugin but again, only Mozilla browsers user this and people are noticing the problem in Konqueror and Opera too.
Well now the problem appears to occur in Debian Sid too. I began having the same issue using Arora on my Meso.
The only psuedo-workaround so far has been to click on the flash, drag off the flash, then click back on the button you want to press. This will usually start a video just fine but a lot of the time you can only do this once, so trying to pause or adjust the volume may not work for you.
Hopefully this will be fixed soon and I can get my non-free fix on!