If you have a message on screen that says NOSRC then then DVR hard drive is failing and the DVR needs to be replaced. You really need to obtain a new DVR as soon as possible. Give us a call at 1-800-COMCAST and we can arrange to get one to you or you can get one at your local Comcast Service Center.
your error is a input or HDMI issue between the box and your TV if your using HDMI.
Sometimes there is incompatibilty issues with certain equipment using HDMI.
You can try using component cables between the TV and DVR to see if the issue goes away.
If it doesn't do it on component but does on HDMI, next step would be trying a different HDMI cable. Check with your TV Mfr's supprot site for firmware upgrades for the TV that frequently fix HDMI issues like this. Sometimes HDMI just doesn't play nice together and you might need to stick with component cables.
Also try changing the video output on the DVR by turning off the DVR and press "menu", that will bring up the user page. Change the output of the DVR to a different setting, like force it to 1080I and see if that helps. Normally it would be on "native
I keep getting an error message "code nosrc". I've called Comcast 3 times and have been walked thru unplugging and restarting my DVDHD cable box. I've also rebooted it numerous times myself. It always fixes the problem, but then it reoccurs in several hours. I've been told that I don't need a new box and that it is a national problem. How can this be fixed?