[s-cars] chirping bird in dash

[michael musmanno]

hey guys,

question about a noise my climate control is making.  toward the end of 
last winter I started to hear a "chirping" noise when I put the heat 
on.  the summer came along and the noise never happened again.  now, 
it's winter again and the "bird" is back.  it's only when the heat is on 
and seems to be sporatic.  it sounds like a chirping bird.  is this the 
blower motor or something else.  any assistance with what may be wrong 
and how to fix it is greatly appreciated.

thanks

mike
'93 s4
'01 a6 4.2