[s-cars] whining replacement heater blower (yes, replacement)

[Kevin Day]

I replaced my old blower with a new one to cure the winter squeaks.  
However, the new blower makes an annoying whine at all times.  The
pitch of the whine varies with motor speed.  This is not the
intermittent squeal the old blower made on cold days.  It's much more
annoying!

Anyone else had this problem?  Defective fan?  Assembly error?
I am not looking forward to removing the heater box again, but the noise 
is really too loud to ignore.

Thanks
-Kevin
("What?  I can't hear you over the HVAC.")