i got the problem as well
i have tried to clean the wiper, using rainex and soup but still got some noise SOMETIMES. Not sure why but I guess the plastic may dry beacause I park my car 24 hours on the street and the sun may dry it up. I try to ask the dealer to fix but i couldnt make the sound in front of them...... =( need to wait the problem to get worse so I can show them

