Improving audio quality
From MEPIS Documentation Wiki
The MEPIS Live-CD uses an 8-bit setting for audio quality and this setting is transferred to your system when MEPIS is installed to your hard disk, but if your sound is working, you can make a huge improvement to the audio quality by lifting the setting from 8-bit quality to 16-bit.
Type "settings:/Sound/" without the quotes into the konquerer file manager address bar, then select Sound System, click the Hardware tab, then change the quality from 8 bits (low) to 16 bits (high) and click the Apply button to restart your sound system.
If you'd like to do a before and after comparison, before you click the "Sound System" icon, click on "System Notifications" then in the bigger part of the window, select a sound to play, e.g. "KDE is starting up", then click the play button in the Actions portion of the window to hear the sound. Close the window, change to 16-bit as above and repeat this procedure. If you have even a reasonable sound card, you should hear quite a difference.