machine won't sleep AND flux won't won't kick in. any advice?

[bobinmurphy]

I see the same thing on my old Mini running Snow Leopard. I've nailed it down to a lot of web sites that load up background crap and leave it running as long as my web browser is left active. I've tried disabling things, installing plugins like Click-to-Flash, etc but nothing seems to be able to stop this. The only thing that works for me is to shut down my web browser before I leave the computer. Then the computer goes to sleep normally on schedule.