Channels Temporarily Off Air - New Orleans

I replaced my DVR box yesterday because the DVR function on the old one wasn't working anymore, as well as the picture freezing and the remote not working. A technician came out and said the problem was the box. I set up the new one, which is a Motorola - CMX3400, yesterday and almost every channel, HD and SD, is showing up as temporarily off air. I called customer support and they reset the box a couple of times and a few channels started working. We tried unplugging the box and plugging it back in, and that still didnt' fix the problem. The customer service rep said my signal strength was strong and suggested just waiting awhile because it sometimes takes awhile for all of the channels to come up. As of this morning, I seem to be able to get one channel to work, but every other channel is temporarily off air. The DVR works, but I can't record anything since the channels don't work. Any suggestions on how to get this resolved? I've had Cox service for years and have never experienced this problem before.