Thanks for participating in our online forum community here! I understand you're inquiring about connecting a PC to a Slingbox. Well, this is not something that the Slingbox was designed for. Any audio/video source that you connect to the Slingbox is controlled by IR (infrared) signal, and that is how the Slingbox communicates with the source device (ie: changing the channel, powering on/off, menu access etc.). And with that being said you likely wouldn't be able to control your PC with the Slingbox, even if you were able to stream video.
Hope this helps!
The Sling Moderation Team
I've not seen this, but I'm guessing the problem is controlling the PC. As the moderater pointed out, the slingbox only has an IR interface to control devices. Therefore you must have somekind of direct input control to the PC like a bluetooth keyboard mouse(which clearly has range issues). Have you tried a KVM extender? That may be cheaper and more specific for your application.