problem play movie back after 20mins

[Scoo8y]

I keep getting problems play movies back on my duo from my hdd, usually after 20mins it freezes then you can here there sound but the picture is stuck.

other times the movies just randomly looses sound

 

[cactikid]

wonder if its to do with cams ,did you need to restart cam for resumption of film?hdd is mounted correctly also?