windows down as well? It had something to do with the windows down, the ANC turned off. I had the sunroof open but the minute I rolled down the window, the sound disappeared. It was just a thought.
More than likely it’s your ANC. Try rolling the windows down when it happens and if the sound goes away, that would be the issue. My 2022 RAM had the amplifier and ANC in one unit and I was having the same issue. Dealer replaced the unit and sound went away.