Panasonic DMR-ES30v Combo- Message of "Check disc for error"

I'm Recording from cable DVR to DVD recorder,start transfer,appears to be copying..return later,..message is "Check disc for error".Do not know at what point recording stopped..how about this,sometimes it records OK,next time I get "Check disc message".

I have used different mfg.discs,Memorex,Sony,Magnavox...The "+" and the "-" format..have used dvd disc cleaner...it boils down to ...sometimes it works and sometimes it don't.....I have no issues with DVD playback.

One thing I have not done is stand and stare at the unit to determine when the recording aborts.