I can’t find any other record of the play attempt in the any of the logs so I can’t see why it’s erroring and of course the DphoneApp.php is compiled so I can’t see the code to try to make sense of it.
I believe I might know the issue now that I’ve read other issues.
This is maybe something that can be made better in the error message. I believe the issue is that auto answer is disabled on the handset. If I’m correct auto answer is required to play a message thus it’s required for visual voicemail and that should be listed online, in the error or when you enable the feature?