Often times, this is a very clandestine and collective effort, and is meant for you not to detect it.
When you walk into the room and they start looking at each other without saying anything, or suddenly shut up, I suspect is the beginning of trouble. You then notice that messages are not getting to you, or your recipients are not receiving your work, for example... And you have no proof of foul play, although it is obvious that foul play has to be involved.
If you address this to your boss, they often say "work that out with your colleagues." So you, as rationally and objectively as you can, address your colleagues and they act clueless.
For one, what could've I [not] done that entices them to do this to me? I know I never gossip. I'm neither a dummy (that they'd love to make fun of) or a ninja (that they'd be jealous of, or feel threatened because I would raise company standards). Goodness - is it my word choice? Accent? That I refrain to curse or trash-talk?
Furthermore, is this a message saying that they don't want me there, want to fire me, but won't, so they'll hope I would resign? If so, is this a valid reason to leave? And if I leave because of that, how do I mask this to an interviewer of the next company? Should I still ask for a reference from my current supervisors knowing they strongly dislike me?
What is the normal way to handle this situation?