You’ll probably need to check the adverts themselves are responsive – if you are using javascript/google adwords etc then they are prefixed sizes and I don’t think adrotate can do anything to make them work better.
Google Adwords does have a new “responsive” ad type that might be worth looking at, else if you are just using images, suggest looking at the responsive settings for each advert, which allows you to specify multiple images for different screen sizes.
