Hi, hawkeyes002 and mrefling
The Pace DC700X HD box is a digital set top box. Most of the times, this issue is related to the connections in use. If you are using the HDMI cable connected on your home network, you will never get the video signal on your Slingbox since the Slingbox (any model) and the HDMI cable are not compatible at all.
The following links will provide you with further information about this situation.
Your Slingbox works fine until you turn on your TV
Finally, keep in mind that the Pace DC700X HD set top box is not included on the supported devices list. This means that even though you get the video signal, we do not have the IR code to control it.