BOSTON -- As iPods become increasingly popular, people are discovering the batteries don't last forever, and you have to be very careful about getting replacements from Apple.

NewsCenter 5's Susan Wornick reported Wednesday that iPods come with rechargeable batteries warranteed for a year. Of course, Apple will replace defects for free, but problems can arise when your battery just gets old and you need a new one.

Apple says to send them your old unit and they'll send you a new one within a week. Your personal songs and files won't be transferred but if you have a model personalized with your name by Apple, you'll get an Apple personalized model back. They charge price: $65.95, which is not bad when you consider new, especially personalized iPods, can cost hundreds of dollars.

But read on and you'll discover you won't get back the same thing you sent in. The policy says, "replacement iPods may be new, used or refurbished."

People spend hundreds of dollars adding bling to their iPods -- everything from sequins to sapphires. Custom kits can cost a lot of money. But if you send that to Apple, you'll never see it again. The policy says if your original iPod was customized by a company other than Apple, "your replacement iPod will not be personalized."

NewsCenter 5 tried to contact Apple, but no one from the company returned the call.