Unable to manually download firmware from asus.com without first changing to Google DNS

[Sky87]

Hi, i have a strange issue. Whenever i'm updating my firmware manually from asus.com, i cannot reach the download server unless i change my dns to 8.8.8.8/8.8.4.4.

This is what i'm greeted with when using my ISP's DNS (My router is set to automatically recieve DNS):

Any reason why this happens when using my standard DNS? I can access all other websites fine.

 

[RMerlin]

I occasionally get this message as well, it usually disappears a few seconds later. I suspect there might be something wrong with one of asus.com's nameservers.