Hi, I think you are referring shared files or published files.
Sorry for the inconvenience. We noticed a bug that when a non-DriveHQ member is accessing files published / shared by a premium member, the ads are still displayed. We are fixing this bug now. It should be fixed in 2 days.
In the meantime, please use our Group Account feature. You can upgrade your account to group account for free and then create a sub-account. Give your friends the sub-account username and password. This way, your friends won't see ads.