I'll weigh in here too. (Software developer here). My signals are all fine and in spec. Everything is working fine. I too am experiencing the freezes. It most often happens to me when I start a program from the DVR and immediately try to fast-forward past the commercials to the beginning of the show. I get a freeze frame (not pixelated, perfectly clear) of whatever was on the screen before I hit FF, sound continues to play normally. If I change channels, sound changes. All functions work, guide, DVR, etc. and I can select any other program, but that frozen frame remains on the screen. If I power cycle the box from the front button, freeze frame remains. Only a reboot (I'm doing it from the Help menu) fixes it.
This behavior began during the past month. I've had this box for over a year. Based on this thread, it all started for people here at the same time. That does not point to a signal issue. That points to a software bug.
My X1 box about screen:
XRE Server version: 1.71.03 01/19/2017 19:58
XRE Protocol version 2.8.0
Receiver Native version 2.6.0
STB Timestamp Thu Jan 5 03:03:22 2017
STM Version PX013AN_2.6p7s1_PROD_sey
(omitted eCM MAC and Device ID from above)
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