Make sure your mx-850 software is up to date via live update.
Go to the ir database, use Comcast Xfinity or X1 ip code set. Cox licensed the Xfinity X1 system from Comcast and branded it contour 2.
Ir and rf seem like they are the best choice from the database but the ip codes work best... They work ir from the mx-850 and rf from a urc Mrf box.
I'm Not an engineer, but I play one on TV. My handle is Tweety but I have nothing to do with the organization of similar name. I just had a really big head as a child so folks called me tweety bird.
