This started happening after an update early in 22. Been hoping some future update would fix it but nothing so far. No matter what app I'm streaming music from or what device is receiving if the music stream starts automatically, like when you start your vehicle up and the phone reconnects, if you light up the screen the music volume will cut by ~50%. The volume is still all the way up on the phone and messing with that won't change anything. Notifications that dim the volume don't have any affect, the volume after those still return to normal. The only way to get the volume back is to crank the radio volume up to very high levels or totally disconnect the BT and reconnect. I've tested this across 4 vehicles and 3 manufacturers, all with different gen systems from 2014-2022 and it's the same for all so it's a phone problem. It also seems to mess with the EQ settings when it cuts the volume
I have a feeling it has something to do with the ***** they try to do to keep people from listening to volume at high levels. I've found one article that suggested you change a setting in dev options but that didn't help.
This just started happening to my S21+ in the last few days (about 13 Jan 2023). I attempted changing 'media volume limit' , but nothing changed.
Happens on my Bose QC earbuds and Bluetooth media connected car. It seems to happen when the screen wakes up.
Tried that months ago, didn't do anything