I've got this awful sound that randomly comes when the heater is on any setting below top notch. It comes and goes at will and random. Sometimes if I press on the gas it goes away too, but not all the time. Its so odd. But if I do turn the heater fan completely on high, or completely off, it goes away, which leads me to think its the heater blower? Thoughts?

Here is the video of it.

 

Sounds like blower motor to me. Purchase an OEM unit. The Four Seasons motors are crap and produce a whistling noise.

 

This should be under warranty yet I would thiink? I have 5 year bumber to bumper.

 

Sounds like the blower motor bearing. Take your glove box out (open it, pop off the down spring assist thing, and press the 2 tabs in left and right) you should be able to hear or feel it more when you are right up against the housing.

It would also be a good time to change the cabin filter

 

Yup, mine occasionally makes the same sound.

And for kickers, this is my SECOND factory blower!! I had to replace the original one at about the 2 year mark of ownership as it failed the same way.