Is my HD Tivo dying??? :(

I have noticed in the past few weeks that when I move from menu to menu, I get a black screen for a second or two.



Is the machine dying? If not, what can I do to fix this? Or should I just ignore it and not worry?



I have a Lifetime subscription which I would really not like to lose! It is my 3rd Tivo - I have upgraded twice (got my first one in 2001).



Thank you!