To change the remote on the Slingbox Solo, you will need to reconfigure the settings on a computer from setup.slingbox.com. You can follow the steps listed in this article to make it a little bit easier, but please keep in mind that you will have to go towards the end of the article before you see the steps for your specific unit:
If you don't see the new remote immediately after you've finished reconfiguring the remote on the iPad application, go into the "settings" and log out temporarily; once you've logged back in you should see the new remote image and have access to your full X-Finity X1 box.
I hope this helps!
Sling Media Technical Support