I have noticed the same problem, starting a few months ago. Especially when watching recorded sporting events, if I try to FF through the commericals (the whole reason for recording the show or game versus watching it live), the recording will frequently jump 15-20 minutes ahead, and then when I try to rewind it jumps back to the commercial.
I assume it is not a glitch or bug, but rather a deliberate strategy by Xfinity, forced by advertisers who won't continue to pay knowing viewers don't watch their stupid ads.
But the result will simply, at least for me, a refusal to watch TV at all. I am not sitting through endless and mindless ads just to watch a show. Nothing on TV is that good.
If I can't watch it on my own terms, I simply won't watch. If more people approached it this way, I suspect Xfinity would "suddenly" fix the problem.
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