Thanks for the feedback. I'll look into that, but I'm not sure how the TV would cause the box to power down. If that's the case, you might try disabling the Anynet+ function on the TV. Anynet+ is our version of HDMI-CEC - consumer electronics control - and is compatible with other Samsung products. But it can also send a signal back and forth to the cable box.
If you feel like trying it, that may be a good place to start. If that doesn't fix it, it may be the box. I'd have know way of knowing definitively, and while the finger was pointed at us, I wouldn't be able to determine either way. But if the TV isn't sending a signal through CEC for the cable box, it wouldn't be able to "instruct" the cable box to do anything.
I hope that helps. Maybe worth a shot.