I have just signed up as i have the same issue has everyone with recordings not working on my 49ks9000. I know that nothing on the tv has been changed but when  scheduled for recording i have seen the odd program has not recorded. So this weekend it has stopped recording all together when set untill now. 

What you need to do is just retune you tv channels, my channels are manually tuned as automatic tune picks up to many channels and can  interfere  With other channels. Im on it now and its 100% working so i think its also to do with the broadcasting side of it that plays a part in it because when a program is set to record and the program before that is runnig late like football its automatically  rescheduled. 

Hope this helps alot of you out there.