I have the 2019 High Country and have heard the high pitch noise. But, mine happens when I am on light throttle at around 36-37 mph, nothing to do with the a/c for me. I can seem to make it happen or make it stop by the amount of throttle I give it at this speed. Maybe my issue is completely different. I have also had the radio center display fail, even let the smoke come out of the wires. I have video of that but I won't share it yet. The dealer replaced the display and the gauge cluster and it just failed the center display again. This hasn't even been two weeks since the replacement.