In Android Pie we used to have an option which upon enabling would give Bluetooth devices their own volume changing capability and mobile device their own.
This was termed as Media Volume Sync.
In Android Q, this feature was removed and also Dual Audio got shifted to Media in Notification Panel.
So here is the way you can enable it without any issue in Android Q.
Enable developer options and there you have setting called "Disable absolute volume".
Enable this option, restart your bluetooth device as well as Bluetooth in your phone.
And it'll give you the same experience as on Android 9.
Thank you.
