Have 3000 miles on my 2020 Explorer ST. Last week all of a sudden loud, pulsing sound coming out of back right speaker whether car on or off. Took them a week and a half to discuss with Detroit and eventually I got it back with new audio module...now stereo sounds shitty like no bass and piped in engine sound gone. I know many say it sounds cheesy but I frankly liked the sound in Sport as I don’t wanna change exhaust and mess with extended warranty. So anyone here have thoughts? Dealer says they have no clue what is causing it-I question whether they changed audio module or just disconnected that rear speaker as they said they were considering doing when I first brought vehicle in. Any help appreciated....