The sound keeps vanishing randomly when I play the CD or the radio. Every few seconds. The CD keeps running, so it's not like it's getting stuck or anything. Gave it to the Bose guys and they said the head was messed up and changed it - except it didn't solve this problem at all.

Take it out and get it repaired. Or you can swap for one from a breakers yard.

https://www.google.com/search?q=2004+kia+amanti+radio+replacement

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You have a bad Rotary Encoder or Display Microprocessor(computer inside your Philips). If you are interested in having it repaired, please visit my website at audioserviceclinic.com. You may contact me there. Thank you.

It sounds like it is stuck in "Demo Mode" below is a link to the manual for your unit:
https://www.manualslib.com/products/Clarion-Db338r-2814176.html

Seem like there is a short in the radio reciever, hence the problem, you could take it your local car udio repair center , or you could upgrade to an aftermarket system which may work out cheaper if your not happy just keeping with the cd.

clen the lens

Hello my friend,what program are you using and what type of music?
First uninstall all drivers and install the latest one.Second check your CPU activity when you are playing music(from task manager ctrl+alt+del),if its too high its a problem.If you are using different music from .mp3 like .ogg or something "not common" you must install the latest codecs.I'm waiting for your reply.

One thing have you tried to pull the CD out?

Press the repeat/random button until it shows "r1" will repeat the current track.
Press the repeat/random button until it shows "rA" will repeat the entire CD.
Press the repeat/random button until it shows "rd" will play all tracks in random order.

Press the repeat/random button until nothing shows will cancel repeat/random playback.

hi Its Error 6 no focus. could be dirty cds. dirty laser. or faulty laser. regards Mark www.carradiospares.co.uk