Asus DSL-N55U With Zen

Tried setting one of these up today to replace a Billion 7800n & something odd is going on with the connection. Web pages load reasonably quickly but only partially. By that I mean that in FF, the web page ident doesn't appear & stays at a circling "loading" symbol while the refresh icon also doesn't appear, staying on the cross. Furthermore, with the Fasterfox Lite Web Page Timer addon loaded, it continues to count, sometimes up to a minute & sometimes continuously.

The more complex the web page the worse it is. ie pages pulling content from several different servers like ad servers or loading numerous images.

I've reconnected the Billion & all is well so it's either an odd setting in the Asus or maybe it's faulty.

Anyone recognise the symptom & have a suggestion as to what it might be please?

Made some progress with this.

Turns out it's the firewall. Using the URL filter to block Google ads, specifically googlesyndication.com, causes any web page that calls it to stall. Now why it should do that on the Asus & not on the Billion I have no idea. It also affects all browsers, or at least IE, FF & Chrome.