To work around this issue, use the HDMI port or the headphone port to connect to an external sound system. Contact the developer of the game to see if an update is available that prevents this from happening.
Mac Pro (Late 2013): Audio from game might stop after wake from sleep
You might not be able to hear the audio via the line out port from some games after waking your Mac Pro (Late 2013) from sleep (when an application is still active).
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