I understand that your virtual remote control is not working. At this point I do not feel that a reset of the Slingbox would help. Usually this issue has more to do with the IR Emitter cable. Here is a couple of articles that will help you troubleshoot this issue once you are at the Slingbox location:
- Slingbox.com - IR Emitter/Remote Control Troubleshooting for Slingbox 350/500
- Slingbox.com - Advanced IR Emitter or Onscreen Remote Control Troubleshooting
Hope this helps!