Very strange networking problem

[Realmz]

I had a problem with my old router that made only a few websites not work, all from the same host (www.baddabinghosting.com). But when I connect directly to the modem it works.

I thought the router was blocking the websites but I deactivated everything that could block stuff in the router settings, I even tried using a DMZ but it still didn't work, I tried changing every parameter that my router has but it's still not working, I tried many firmwares, everything.

So I thought my router was defect so I bought a new one, after many months of it working properly, it now does the same thing as my old router, I have not changed any parameter, I did not even enter the router config in a few months. The exact same thing happened with my old router, it was working fine and then for no apparent reason some websites from www.baddabinghosting.com stopped working. Again, if I connect directly to the internet it works.

If I do a trace route it reaches pretty far until the 20th jump it times out indefinitely.

Same problem in Firefox and IE.

I tried on many computers in my LAN.

Yes I did try many MTU settings.

Also, if I use a free proxy like http://www.youhide.com/ it works, I can reach the sites but its slow as hell of course.

I'm out of options, I fear if i buy a new router again it will do the same thing, I don't understand this.

This is a very big problem because www.baddabinghosting.com is the hoster of my website, I can't reach any websites from that host or the hoster' site itself and the ftp, nothing.

Sorry for the long read but I had to explain that situation in detail, please help!