Time capsule and Safari getting stuck loading a webpage

Since I installed Time Capsule I noticed that pages that I load in Safari (and Firefox too) get stuck at a certain point during the loading process. It's never the same point but it's always a HTML resource, like an image or a javascript file.

It gets stuck when it says "Loading 'webpagename' complete 9 of 24" - and it stays there. Sometimes it manages to load completely but more often than not it gets stuck at a random point.

Did anyone else notice a similar problem?

Almost instant update:

I use Time Capsule in bridged mode. With an other router connected to my cable modem and Time Capsule acting as a bridged access point. I originally had the other router connected to a normal LAN port on Time Capsule. But now I moved the router to the WAN port on Time Capsule and the problem looks like a thing of the past. So the WAN port seems to have a different configuration, even in bridged mode.