Lowrance GlobalNav310 Problems

[FlyingV]

Maybe someone out there can help me? Last year my back light went out. The unit still worked but it was an inconvinience at night. This year, the unit still works but the MODE key does not. Also, when I press the Menu key and the Menu screen comes up, the UP arrow key does not work, I can only scroll down. The UP arrow key works when I am scrolling the Plotter screen though.
This is the second Lowrance/Eagle unit I have had problems with. I think it will be my last. Anybody got any ideas what could be wrong? I thought maybe the keyboard was dirty but I can't get the thing apart to check it. Anybody have any opinions on other GPS units?
Thanks

[snowfighter]

I had a 310 last year ,it would shut its self off and wouldn't start up. Called Lowrance and they said the 310 can't be repaired because of the way its put together. They let me upgrade to the 2400 which can be repaired if needed, $225.00 like it better.