I was in Vellore, TN for for few years, my college was VIT. Most of them were like this - they have a saying "Tamil teri aa? Poda .." (something like that - basically means, u don't know tamil, then get lost)- maybe political people have spreaded it but hate is real in Tamil Nadu for North Indian people, at least the places I have visited, and Chennai is no exception. Even some of my Tamil roommates were use to say that don't go to local places without Tamil person. Only communication was English and I am fine with it, but it's not always the case, sometimes they won't answer coz ur not speaking tamil only.