Hmm,
if it is still under warranty, then its probably a claim.
My advice is to get it evaluated by a Dealer independant trans specialist first.
Even if it costs you a couple of dollars for his time to assess the problem, and it turns into a warranty claim, at least you will have the benefit of the advice of a person who is not interested in making the 'company' happy.
Dealer employee's are trained to push it back onto the customer rather than have their employer pay. You may be surprised, it might only be an electrical fault that costs you $50. this has to be cheaper than what your down time with a dealer might be!
Start with the independant transmission specialist. he may say its stuffed, take it back under warranty. If he does, and you get it fixed, and he doesn't charge you for diagnosis time, then at least return with some beers for him.
Diagnosis is the hardest to charge for, and many people don't even after 2-3 hours. Keep us posted on how you go.
Cheers
Jas