Casio makes a variety of digital keyboards. As with any electronic device, problems will occasionally arise. Many of these problems are solved quickly with a little bit of troubleshooting. Casio has an online support service available for problems that cannot be solved at home. The following list of issues and solutions is from the manual for the PX-3 digital keyboard, which is available on Casio's website as of January 2011.
1 Make sure the volume knob is turned up if no sound comes out of the speakers or headphones. If that doesn't work, check that the "Upper 1" zone setting is set to "Int On." Find the row of buttons with "Zone Selector" above it and press the first button. Then press the "Int/Ext" button to cycle through settings until the two lights above the zone button are lit up.
2 Turn the digital piano off and back on again if the keys are playing the wrong tones or if the tuning is incorrect. These settings can be changed, but will be reset when you turn the keyboard off.
3 Turn off the backup feature if something on the keyboard sounds strange and does not resolve itself when you turn the keyboard off and back on again. If the backup feature is on, all changed data will be saved when you turn the keyboard off. Turn backup off by pressing the "Function" button and selecting the number 8. You can then select "BackUp" and turn it off or on. After changing this setting, turn the keyboard off and back on.
4 Check the format of your music files if you cannot play a file from an SD card. The keyboard may not support the format your file is in; the PX-3 supports only Format0 or Format1 SMF or CM2 format files. SMF stands for Standard Midi File, while CM2 is a file specific to Casio products. Audio files such as WAV and MP3 are not supported.
5 Check for error messages on the display when a problem occurs. Many of these messages occur with the use of an SD card. For the message "Format," first make sure the card has a capacity of 2GB or less. Format the card by inserting the card into the piano, pressing "function" and then "7" and using the "<" and ">" buttons to display "CardFORMAT." Press "Enter" and then "Yes" to format the card. If it still does not work, try a different SD card.
6 Delete some files on the memory card or insert a new card for the message "memory full." If you are not using a memory card, delete user data from the keyboard's memory. To delete files, press "function" and then "7." Use the "<" and ">" buttons until "FileDELETE" is displayed, and then press "Enter." Use the up and down arrows to select the file you want to delete, and press "Enter."
7 Check your manual for a full list of error messages and common issues with solutions. Manuals are available for download in PDF form on Casio's website. Casio also offers an online repair request and a locator for repair in your area.