If you are using a powered antenna or powered antenna preamp in your system, there is a symptom that is becoming common. Symptom is, 'I can only record while the TV is turned on.'
It's becoming quite common for preamps to operate on 5vdc, and, the amp/preamp gets power through a USB power cable. You have a choice to connect the USB power cable to the provided USB wall power adaptor, (Like a cell phone charger) or, you can connect the USB power cable to a USB port on your TV. If you have it connected to the TV USB port, the amp will lose power when you turn the TV off.
In the scenario above, if you have programs setup to record, and your TV is off, your DVR may get poor or no TV signal. Your recordings could be of poor quality or no recording at all.
Make certain that the Time, Date, and Time Zone are setup correctly.
Note; If you turn the CM-7004 power off with the remote control or the front panel button, or, choose "Power Off" in the 'Standby' setting, your 'Scheduled Recordings' will not record. You can find more information here.