I had exactly similar problem with my HD DVR of RDTV,
i think problem is that recent software update before propsed vishwaroopam premium was the culprit in my case..that update might have softbrick the STB, its not able to show any channels for me too
but its showing 413 loksabha tv ,556 gyan darshan and Rajya sabha 414
you also check whether there are coming not
I have been told that i will be getting replacemet in the form of HD box for replacement with HD DVR, HD box yet to come,they are saying out of service
In compansation for downgrading from DVR to HD,they will credit 3 months balance amount of my existing pack to my account
Technician who came to my house told that he has one more DVR box compliant and two more HD Boxes to check for complaint
This software bugged many boxes-
As a epidemic all HD and DVR boxes of RDTV failing- god knows reason
But enough is enough with RDTV, i moved to Videocon HD DVR..