When of my biggest pet peeves is not that notification sounds play while listening to music, but that they briefly power its volume. Its like dancing in a club and you get a notification about your uber eats and so the dj tells everyone to quiet down for a bit so that you look at the message.
I am pretty high while writing this, so, just to be safe, here are similar issues: https://android.stackexchange.com/questions/204153/disable-or-change-audio-ducking-lowering which was deemed answered by https://android.stackexchange.com/questions/199918/stop

-notifications-from-briefly-lowering-media-volume.
Use a music player that has a setting for it. I’m a poweramp fanboy
Seems like your links answer the question: it’s up to the app playing music, and there are some suggestions of apps that let you choose.
I was always the guy who made custom notification sounds for every app, going back to the flip phone days. Until I got a Pebble watch back in 2016 and permanently put everything on vibrate-only.
Last year, I went back to a regular watch and turned on the notification sounds again…
Anyway, I turned them all off a few days ago for some reason, and just haven’t cared to turn any of them back on. It’s been really nice. I think I’m going to just set a notification for phone calls, and texts from my wife.
I miss having a phone where vibrate was useful. I’d really prefer that over sounds.
My OG Droid would wake the dead.
😕
A useful vibration is one you can feel, not hear from across the room.



