dns filtering on switch stopped access to google docs

I just found this out when my kids complained about not being able to access google docs (docs.google.com) to do their homework.

Apparently having the switch on for dns filtering, even though i had no service selected, was causing a timeout error reaching this web site. It did not stop me from reaching google drive, just google docs. Strange. Turning the switch off resolved the problem.

I have an asus AC88U