Has the virtual remote ever worked with this set-top-box? Usually it's just a simple matter of IR Blaster positioning. Below are some articles that should help you resolve this issue:
- Slingbox.com - IR Emitter/Remote Control Troubleshooting for Slingbox 350/500
- Slingbox.com - Advanced IR Emitter or Onscreen Remote Control Troubleshooting
- Slingbox.com - Set-top box not responding to remote commands
Hope these help!!!
Sling Media Moderation Team