i'm in the same boat.....
I have the new comcast box and a $79. harmony remote. (geeksquad programmed harmony to "learn" comcast box, wasn't on harmony website as of 4/01/13)
All of my equipment is hidden in my closet. TV and IR sensor device in my living room.
Currently, i have an IR sensor "eye" taped to the front of my comcast box.
However, when trying to work channels, with remote pointed directly at my IR receiver on the front of my tv, its very sluggish when trying to change channel/work guide. Very frustrating.
i've tried to move the IR sensor "eye" on the cable box to a different location, but its still kind of sluggish.
Maybe the "eye" on the cable box isn't in the right position?????
Trying to find out where the IR sensor is on the comcast box. i haven't tried comcast yet. Will continue to search web.
LET ME KNOW WHEN YOU FIND WHERE THIS IS !!!!!!!!
I have not tried this on the main X1 box (PX001ANM) however.
I got a brighter flashlight, and found another little hole visible on the far right side. It's about 1/2" to the left of the XG1-P printed near the power button.
So far my blaster seems to be working much better in this spot. I have hit button after button, and cannot get it to fail to process a button press.
That large port near the center actually looks more like an emitter of some kind. It looks like an LED. Maybe that is for controlling other gear, and is not activated yet?
I found another visible port about 1/2" or 1" to the left of the larger eye in the middle. I am experimenting with that one now. I'll see how it works for a day or two.
Has anyone been tweeting the sensitivity of the buttons after moving?
I have recently gotten the X1 and placed my IR emitter toward the left of the large ??? in the middle of the red plastic. It has been working fairly well, sluggish at times but it does work. The only commands I cannot achieve are Power On/Off. Door open/door closed makes no difference! My remote is is the Harmony Touch. I have not been able to find anything about adjusting the X1 remotes to function as either IR or RF. The Xfinity remote works like an RF, very fast with either doors open/closed. So, why is there so little information available about this platform, these remotes and how to duplicate their performance in a Universal???