Hay there guys, today I was driving my Subie and I noticed that a weird squeaky high pitched noise (that I have never heard before) came up when I turned on the interior air nob (just to get the air from outside, not the air condition). I think that one of lines may have busted, but I am not sure. Can anyone help me with this? I did a search and I read that I may have a leak somewhere and to not turn on the interior air until I get it fixed.