[Q] capacitive buttons

Greetings friends! :)
I have a small problem with my note :)
I just bought it today, yes its used....and i'm third owner now...
its international model, N7000...running ICS 4.0.4 atm...
but my capacitive buttons dont work, or light up :/
i heard and read about it that u can disable buttons etc...
sooooooooooooooo....can you guys help me that i can see if they are disabled, or what happened with them ://
if that wont work, what app can you recommend to me to use onscreen buttons :)
Thanks a lot!!
and sorry for double posting or something similar!
Best regards to you all!