I recently noticed that my car is making a consistent noise when AC is engaged. Furthermore I found that this noise occurs only when car is hot. Belt doesn't seem to be slipping.
Car is 16 Subaru WRX. Found several similar issues online for Forester and Crosstrek though. Here's one similar noise problem on a Forester https://www.youtube.com/watch?v=cQJuVlMgGJs
Nobody seems to have a clear conclusion of reason or fix. Before I take it to the dealership and spend $1,200 for a new AC compressor, is there any budget friendly fix I can try at home?