Thank you. It's a new construction and the builder seems to generally pick really good subs, and I'm pretty sure whoever installed it did the entire house, so they should be familiar with it. I'll give them a call.

Edit: Update to this. I cut the circuit breaker and opened the unit and something was clearly wrong with the blower motor. Mountings and bushings etc all looked fine, but rotating the blower manually was rocky. It seems like a bad bearing or something but I'm no expert. The tech came out and confirmed in about 15 minutes the blower motor needs warranty replacement. Unit is less than 8 months old, he said it's rare but he's seen it before. I kind of want to do a teardown but not enough to buy it. Tech said it was OK to run, and I did that up until yesterday when it sounded so bad I was afraid it was going to grenade the whole box and stopped using AC. Temps close to 100F so hopefully he gets to it soon. I'll be sure to have him run it before he leaves. Thanks again.