If you see this error, please:
#1. Update iTunes to the latest version
#2. Please make sure the songs you want to convert are all downloaded in advance
We highly recommend that you download the Apple Music songs on your computer (local folder) before the conversion starts. By doing so, there will be less chance of getting the "Playback error".
Note: If a small iCloud downlaod button appears in iTunes music library, it means a song has not been downloaded yet. You can click at the iCloud download button to download the music on your computer.
#3. Please try to re-authorize iTunes on your computer
On your iTunes, click Account > Authorizations > Authorize This Computer... Then, log in iTunes with the Apple ID that you use to subscribe to Apple Music. Finally, restart Apple Music Converter.
#4. Please make sure that you are using the latest version of TuneFab Apple Music Converter.
If you are not sure, you can directly update your software by downloading it from our official website.
If these 4 methods are failed to fix your problem, please submit a request with the basic information of the TuneFab Apple Music Converter and iTunes and with the screenshot of the play error of TuneFab Apple Music Converter.