Random Bluetooth problem with iOS 15.8.2, iPhone 7

The fact that the Music app randomly starts when you connect to your car's Bluetooth suggests that there might be a glitch in how the iPhone is interpreting the connection or in how the car's Bluetooth device is communicating with the phone, for further mitigation follow the next steps as they can potentially resolve the issue:

1. Forget and Re-Pair the Bluetooth Connection: Go to your iPhone's Settings > Bluetooth, find the entry for your car's Bluetooth device (Monster, MCC9-1033), and tap the "i" icon next to it. Then, select "Forget This Device." After that, restart both your iPhone and your car's Bluetooth system. Once they've restarted, try pairing them again and see if the issue persists.
2. Reset Network Settings: Sometimes, network settings can cause Bluetooth connectivity issues. To reset your iPhone's network settings, go to Settings > General > Reset > Reset Network Settings. Keep in mind that this will also reset Wi-Fi networks and passwords, so you'll need to reconnect to Wi-Fi networks afterward.
3. Check for Software Updates: Make sure your iPhone's operating system is up to date. Sometimes, software bugs can cause issues like this, and updating to the latest version of iOS can potentially fix them. Go to Settings > General > Software Update to check for and install any available updates.
4. Contact Apple Support: If the issue persists after trying the above steps, it might be worth reaching out to Apple Support for further assistance. They can provide more specific troubleshooting steps or recommend any potential hardware repairs if necessary.

You should be able to diagnose and hopefully resolve the Bluetooth connectivity issue between your iPhone 7 and your car's Bluetooth device.

Resources:

• Apple Support: Official Apple Support
• iPhone User Guide: iPhone User Guide - Apple Support
• Monster Support (for troubleshooting car Bluetooth device): Monster Support