Strangely the same.
http://forums.techguy.org/networking/1034813-my-home-wi-fi-wont.html
While you write you checked the firewall on the router, did you turn it off?
Videos on Tumblr won't play on my wifi. Both my laptop and phone are having this problem. When I switch to 3G on my phone, the videos play. And when I am using a different wifi network, they play then as well. I can't figure out what the problem would be with my wifi. I've checked my firewall settings and stuff like that. There's no security software that would be blocking them. I've tried a lot of different things but nothing has worked. Does anyone know what the issue might be? It's only videos on Tumblr that don't play. Videos on other sites play just fine.

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