@heiner I have removed the second and re paired the first. If I put the Bluetooth favorite to the playlist manually it plays the sound. But the favorite is not put to the list automatically.
I have removed the first mobile and uninstalled the plugin. rebooted. installed the plugin. rebooted. And paired the second mobile. The favorite is automatically put to the playlist again. But it plays for only 3 to 4 seconds and without sound, when the mobile is connected or when it plays sound.
I removed the second mobile, and paired the first mobile. The plugin works now as it should. It puts the favorite automatically to the list and plays the sound.
On a second connect it still started the favorite automatically, but stopped after 3 to 4 seconds. When I klicked the play button in LMS it played the sound.
I have noticed a difference in the two devices connection settings. The first gives the option to connect with high audio quality (AAC).