Flash Player crashing in Firefox

Hello all, My friends and I have been having a problem with Flash Player crashing repeatedly, which of course kills the voice/video chat. This feature was working fine a couple of weeks ago, but now we all seem to be having the same problem. The voice/video gives a very long "Loading..." message, and then when/if it starts to work, it crashes in very short order with an error message of "Adobe Flash Player has crashed". I am on AMD Phenom II 3.2 gig processor, 16 GB RAM, 1GB Radeon HD5760 video card, running Firefox 13.0.1 in Windows 7 SP1, with Adobe Flash Player version 11.3.300.262.