Krystal0719 Said:
"iOS 15.1.1 update - volume muting itself while listening to Spotify in the car: Since I upgraded to iOS 15.1.1 while I am in my car using Bluetooth to stream Spotify every few minutes it will turn my phone volume all the way down. Sometimes it does it more, sometimes less. [...]"
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Two Things to Try:
A. Start with a Restart:
Restart your iPhone, and see if it then is fixed.
B. Report this to Apple:
Do your part: Let Apple know what is going on here. Provide them with feedback on this. They may not get back to you directly, but the more feedback they received on this, the more they will know what is going on, and what needs to be fixed in updates to come.
- Go Here: Feedback - iPhone - Apple
- Comment: that it is after installing iOS15 when the issue began
- Select: "Bug Report" for the "Feedback Type"
- Proceed from there aw necessary