Thank you for reaching out to us on our online Answers forum. I can understand the issue here where you are controlling the wrong input. The problem that is happening is that the input hooked to the Slingbox is actually controlled by a UHF/RF remote control and the input going to the TV is controled with an IR control. The Slingbox only controls the cablebox by using IR signals so you would have to change the remote for the input to the TV to RF and the remote to the Slingbox to IR you would have to contact your cable provider about switching them over.
The Sling Media Moderation Team