DVR programs I recorded skip or black out or other programs can be heard throughout the recorded program

I am having a problem with my DVR I have only had it a few months.I just returned last night from being away for about 10 days and recorded numerous programs. All of the programs I recorded skip or black out or other programs can be heard throughout the recorded program but no video is shown. The screen freezes blacks out and then stops and shuts off. A lot of programs just did not record at all is awfully frustrating and it seems that a lot of people are having these same problems. What's the fix?