I recently purchase a 2019 Urus and love it except for the sound that happens as I decelerate and it drops to between 1500 and 700 RPM. It is on the drivers side in the area under the front speaker ( thats not it) and appears to be coming from the firewall or maybe heat shield, and sounds like a low pitched rumble lasting about 4-6 seconds. The dealer can’t find it, and replaced the exhaust brackets to no avail. HELP! It’s driving me crazy. Any ideas?