Wow. This thread is an eye opener for me and may solve what has been an ongoing annoyance for me. I had professional sound deadening done recently at an audio shop on my 2020Adavnce when they upgraded my speakers. After that work, the cabin has been nice and quiet...except for a strange low rumbling noise that comes on randomly, gets louder, and then shuts off suddenly. It vibrates the steering wheel when it get loud enough. I happens mostly at mid speeds, but occasionally on the highway. Seems so random. Not really happening when the engine is under load or when the car is shifting. Seems better for some reason when the sunroof or windows were open. Thought at first it was a wheel bearing, but I'm wondering if the sound deadening didn't confuse the ANC system. This would make sense to me given the timing of when the issue started and since the noise seems really unnatural to me. I have an appointment this week with the dealer for them to investigate. Will definitely be asking about the ANC, which I had no idea even existed until just now! Anyone know if it can be electronically adjusted or re-calibrated?