.m4a file cannot be played

Hi @Morihiko_Inamine,

In order for Roon’s @support team to better assist you, please provide a brief description of your current setup using this link as a guide.

Make sure to describe your network configuration/topology, including any networking hardware currently in use, so they can have a clear understanding of how your devices are communicating.

What trouble shooting steps have you tried, for example rebooting the Roon Core?