A multi-disc CD player has a laser that reads the discs you play -- and needs to be free of dust and any other obstructions. It's a good idea to clean your CD player after about 30 hours of use or if your player starts misreading discs. A can of compressed air can get the dust out of the magazine or carousel that holds the CDs, but cleaning the laser without knocking it out of alignment requires the use of a cleaning disc.
Place the CD lens cleaner, label side up, into your multi-disc changer.
Play the disc.
Let the cleaning disc go through its cleaning process, which will take a few minutes.
Remove the cleaning disc when the process is complete.
Put a music CD into your changer and press play. If the disc plays without any problems you are good to go. If your player still malfunctions, check the CD for scratches or try a different CD. If problems still exist, run the cleaning disc again.
Chronic malfunctioning could indicate that the laser has been knocked out of alignment and your CD changer needs professional repair.