A/C Something Is Not Right?

[LeeB]

First off I want to thank those of you that helped me in the past with my A/C problems as it turned out it was a simple fix.
I have a 2004 Workhorse 33V. The something that ain't right is as follows. When on MAX A/C on high the fan blows. However when on Regular A/C the Fan blows faster????


Also I am getting a high pitch whine coming from the A/C somwhere.. When I switch it to defrost it goes away????? Vacuum leak perhaps or a door stuck? I have looked and looked but I can not pin point it. Could be because I wear Hearing Aids so it makes it hard to Pin Point. Thanks LeeB