When I turn on my air to full I get this irratating whistling sound coming out. It happens on all my modes, windshield, facial, etc. They did put a brand new blower in my car this friday which was supposed to solve the problem. Any indeas

 

A vent is closed just enough to cause the whistling? or there is some other obstruction, maybe some leaves or something buildup.

 

I wish I had a whistling sound that increased with RPM .. ..