I am expericing very annoying difficulties with my pioneer cd player. It will no longer eject the discs correctly. Also i live on a gravel road and dirt must be getting in it becuase all my cds come out with dirt on them how can i remedy this problem as im moving off this road soon. Also its less than a year old it a DEH-P5900IB

 

If it is less then a year old, and you got it at an authorized dealer, carefully blow out all the dust, and take it in for warranty.

When the HU was installed, was a back support installed on the back of the unit?

Any dirt/dust in a CD player is not a good thing, when there is so much that discs come out dirty you have a big problem, removing the HU from the dash and opening it up, [remove cover(s) and using compressed air and blowing out the dirt/dust may solve your problem, either way, warranty does not cover excessive dirt/dust in the unit so it would have to be removed before taking it in for warranty coverage.
Hint, look for "tamper tape" before opening the HU, [removing covers]. 94

 

pioneers have 2 rollers that roll the cd in and out. dust sticks to them bad and will cause them to not grasp the disc. you will need to remove the top cover, take the 4 mounting screws out of the cd mech, pick up mech and unplug ribbon cable. now if you look in the front of the mech you should be able to see the rollers. take a Q-tip and some rubbing alcohol and clean them good. its also a good time to clean the laser lens while its apart. do this with a Q-tip and water. BARELY dampen the Q-tip and very gently swab the lens on the laser, carefull not to damage the wires suspending it in place. then turn the unit over and make sure the grease on the lasers slide rails is still slick, if not find a suitable grease and put a little on the rails. if this doesnt help you will have to send it in to a service center.