Quoted exactly from Apple's Warrenty for the iPod:

"Damage to the Covered Equipment caused by accident, abuse, neglect, misuse (including faulty installation, repair or maintanence by anyone other than Apple or an Apple Autherized Service Provider), unauthorized modification, extreme environment (including extreme temrature or humidity), extreme physical or electrical stress or interferance, fluctuation or surges of electrical power, lightning, static electricity, fire, acts of God or other external causes;"