Are you still having this issue? Can you tell me a bit more about your configuration? What kind of cables are you using to connect your Slingbox? Which model Slingbox do you have? Make sure your connections are tight and secure. You can always try another set of cables. Here's an article that might shed some light on the issue at hand. Slingbox audio issues: Basic Troubleshooting
I hope this helps!
Sling Media Forum Moderation Team