Tech swapped out SD box for HD 2 hours ago. Tech left and new box started rebooting. Spoke to Customer service who had me unplug the new box. Worked fine for about 5 minutes and started rebooting again. The TV never comes back on. Just in a constant reboot.
How is the box connected to the TV?
You should be using a HDMI connection. Not the coaxial cable.
Also check the coaxial connection to the cable-box. Make sure end connections on the cable have not loosened. The box may be resetting because it is not getting a good signal coming to the box. The box takes about 15 minutes to fully load code. You might need to turn on the box again after the 15 minutes. My Cisco RNG150N works that way.
If anything I suggest you pop by a retail store and get the equipment swapped.