Car cd player kipping

CD disk bad. (audio disc bad or scratched)
or CD dont really support disk media format , is this a CDDA or MP3
some early MP3 disc drives do MP3 very poorly
or skips when you hit bumps in the road.
only that disc skips.?

That's normal in most cars!

CD skip when hitting a bump is common in factory or low end players also if your player is not secured properly the disc will move slightly and the laser loses it's place, so to speak, for a second. The radio thing could be a loose antenna wire connection, possibly related to the fore mentioned problem. Hope that was helpful.

The laser in the cd player may be dirty or has gone bad and can no longer read the disc.

This can happen for several different reasons. 
1. The dampers (oil filled shock absorbers) are leaking and need to be replaced. You can check this by taking the unit out and opening it up and then remove the CD deck. In each corner of the CD deck you will see a small rubber looking device that the internal mech floats on when a disc is engaged. It is attached to the internal mech by only a small metal peg. Check each corner for these. Make sure they are not leaking anything. It is usually a white looking substance that feels like grease. Ant time even one of them go bad or get popped out of place, it will skip on every bump.
2. Try cleaning the lens. Sometimes a dirty lens will make the CD player skip much easier than it is supposed skip. You can buy a cleaning disc at most retail outlets that sell CD and DVD players. Run it as directed in the instructions. 
3. one or more springs are streched out a little. These mechs have many springs in them and if one is a little streched it will cause skipping. If you find a loose spring, it will need to be replaced.
4. Weak laser output. A weak laser will also cause a unit to skip. If this is the case the laser pick up will need to be replaced. There is no fix for a weak laser other than replacing it.
5. Spindle motor problems. A spindle motor with even a tiny bit of oxidation in the windings can cause skipping when you hit a bump. 
There are also a few other things that can cause this same issue. It is not an easy thing to fix without some training on this type of equipment. 
Is this an "Aiwa"  or is this a factory unit that cmae with the car when it was brand new. I don't think that Aiwa is an OEM radio, but I could be wrong. I fix aftermarket radios only.  So I am not real familiar with all the OEM models. 
If this is an aftermarket Aiwa radio, you should take it to a service center to get an estimate. If it is an OEM radio, it is most likely going to be very expensive to fix and a good aftermarket radio would really serve you better. 
I am sorry if this is not the answer you were hoping to get, but it is the truth so I hope you will not punish the messanger for bringing bad news.
Anything less than a "helpful" rating is a very bad rating meaning that you got no help or that the help was not related to the problem. I spent a lot of time putting this information out here for you for free, so I only ask that I get a decent rating for my trouble.
If you require any more help feel free to post another comment on this thread with any questions you may have. I will be happy to answer them for you.
Dave

Does it cut out when you are listening to the tuner as well as the cd player? If so, you have a bad connection somewhere. Sometimes the solder joints inside the radio can be cracked and will cut out when you hit bumps. May be a wire that is a little loose. Check all the wiring.
If it only cuts out when you are listening to the CD player, you may need the lens cleaned or the laser replaced. Sometimes the cd player cuts out because the unit has too much wiggle room and it bounces a little when you hit a bump causing the cd to skip or cut out. and there is always the dirty CD. Try cleaning the CD's with windex and a soft cloth like a bath towel. It works great for me and is cheap. Fingerprints can and will cause a cd player to skip.

Has it always done this, or is this a new problem? If this is a new problem you may need the unit serviced. It may need the lens cleaned, or laser replaced. If the laser is getting weaker it can do that. They also have these small oil filled dampers used like shock absorbers. If one of those is torn and has leaked a little oil out it will skip much easier. They also use springs to support the cd mech, if a spring has streched out or come loose, that can also make it skip on big bass hits.
You can always try putting some foam or something around the radio to help keep those heavy bass hits from vibrating the radio. But then the radio may get too hot.
Make sure the radio is very secure in the dash.
If this problem has been going on since you installed the radio, you have an installation problem. The radio is a little loose and prone to move around a little.

i bought new songs on itunes and i got a notice when i was syncing my ipod that said "the file or directory is corrupted and unreadable" and now my ipod skips over the songs i just bought.

try cleaning the lazer lens, also remember it is old and is most likly toast., the longest I ever owned a deck that didnt go out was 4 years.

Burned ones? Or do "real" CDs do it, too? If ALL do, then the laser was damaged or misalligned and will have to be serviced.