Can I play music or use applications while charging the battery via USB connection?
If you would like to play music or use applications on your Walkman player while charging the battery using a USB connection, tap Turn Off USB Storage once the connection with the computer has been completed. You can also drag the Status Bar on the Home Screen, and select Turn Off USB Storage under the Notification Panel.
If your Walkman is connected to a computer as a media device (MTP), you can play music or use applications.