Copied from other comment:

There’s an app for that: https://github.com/zacharee/Tweaker

You’ll need to use adb to grant special permissions that an app can’t request on its own.

adb shell pm grant com.zacharee1.systemuituner android.permission.WRITE_SECURE_SETTINGS
adb shell pm grant com.zacharee1.systemuituner android.permission.PACKAGE_USAGE_STATS
adb shell pm grant com.zacharee1.systemuituner android.permission.DUMP

• Audio & Sound --> Disable Safe Audio Warning --> Disabled
• Persist Options --> Checkbox Disable Safe Audio Warning