White screen when accessing Music DB

My cocktail x10 boots up OK and all functions work until I try to access the music database and play something I have ripped. The screen then goes white and nothing else will work. The only thing to do is to turn the unit off using the on/off switch at the back. I can still stream from the cocktail to another player in another room so the hard disc itself still seems to be functioning, just not my access to it from the unit itself. Can anyone help please? Thanks