EDIT: I did try to plug in my wired earphones into the jack (never doing it again!) and it also produced hollow audio. I'm just trying to think whether this is a software issue on 11.0.1 for 6S Plus? I know a few people who have 6S Plus but still running on 11.0 so will get back to you whether it is an isolated issue or not. It seems like the audio quality of my AirPods has suddenly gone worse when it’s running on my iPhone (11.0.1). I can tell the difference as the audio is far more hollow. If I pair AirPods to my Mac the audio is fine and crisp, as it was meant to be. I’ve yet to test my AirPods on someone else’s phone running an earlier version than my iPhone (in case if it is an isolated problem). I’m 100% confident there is a substantial difference in the audio quality on my phone and my Mac right now. The audio would be comparable to $5 earphones you can find near the checkout. I can’t recall exactly when the AirPods began playing hollow audio on my phone but it clearly started last week. I will try to plug in regular earphones which will narrow down my issue. However the port is rather stuffed as I dropped the phone a few months back which has affected the circular shape of the jack (see EDIT at the top). Any suggestions? — Also note that EQ is off on both iPhone and Mac.