Morning MMOers

I have been having an issue with my Xbox 360 recently which has been annoying me.

When I load things from the main screen, whether its an app like LoveFilm, Iplayer etc or a game from Disc or Harddrive it sometimes (id say 1 in every 5 loads) gives me a black screen and just makes a whirring / ticking noise like its trying to spin a disc and will just stay like that.

It doesn't freeze as such, because if I hold down the Xbox button on controller I can turn the Xbox off but not return to the main screen.

Its not a major issue at the moment as a restart fixes it but I wondered if anyone knew what causes it or whether it could lead to worse problems?

Also iv noticed its not an overheating issue.