the forward, reverse, up and down not working?

i cannot change the songs or go to am and fm as the main large wheel doesnt seem to be working. the songs can be played fine but cannot skip from one to the next of back again. can i fix it my self or do i need to send it into be repaired. its not under garenty as i brought it second hand. please help as i love this its my baby. if it a repair joby have you any numbers and addresess to send it to. many thanks jennny
it is a kenwood cd player xx