Thank you for posting in the forums! I understand that you are having an issue with the audio not working on the WDTV SlingPlayer Application. Now this certainly is a strange issue. I would like to suggest doing a soft reboot on the Slingbox by unplugging it for 10 seconds, then plugging it back in. Please get back to us if this doesn't resolve the issue.
Thank you for the feedback!
Sling Media Forum Moderation Team