Well, there seems to be a solution by your own admission. Remove the DNS hack.
Content filtering via manual DNS is a very poor choice, as you are breaking DNS and could be causing all types of HTML rendering problems depending upon how a site formats content.
If you have a problem looking at ads for some reason, which BTW pay our rather expensive hosting bills (multiple servers, bandwidth, support, contracts, etc.), then you could try using a HTTP content filter proxy or similar dedicated filtering solution.