In a rare admission that one of its products has a manufacturing defect, Apple has issued a warning on its website warning that anyone that has purchased one of its first iPod Nano MP3 players to immediately stop using it, check its serial number against its database and identify if it can be sent it directly back to the company so that it can issue a replacement, free of charge.

As noted by 9to5mac, the company has said that it has identified that in very rare cases, the battery on the first iPod Nano may suffer from overheating issues and pose a risk to those that use it. To clarify, Apple says the affected iPod Nano’s were sold between September 2005 and December 2006.

Apple details the issue:

This issue has been traced to a single battery supplier that produced batteries with a manufacturing defect. While the possibility of an incident is rare, the likelihood increases as the battery ages.

Apple recommends that you stop using your iPod nano (1st gen) and follow the process noted below to order a replacement unit, free of charge.

Note: This battery issue is specific to the iPod nano (1st gen) and does not affect any other iPod.

The replacement program is in effect in 20 countries worldwide, inviting those with an iPod Nano to click onto its replacement wizard to identify whether it is one of the affected units. Users must enter the serial number of the MP3 player and if eligible will receive a replacement within 6 weeks of sending their current iPod.

Screen Shot 2011 11 12 at 07.46.45 520x264 Apple finds overheating issue with 1st gen iPod Nano, offers free worldwide replacements

However, engraved units will not be returned personalised:

If you have a personalized iPod nano, you will receive a non-personalized replacement. Make sure to use iTunes to back up any data on your current iPod nano before sending it in for a replacement unit.

Apple also provides additional information on how to identify an eligible unit, detailing that the replacement will be warrantied for a period of 90 days:

Identifying an iPod nano (1st gen):

It has a black or white plastic front and a silver metal back – later iPod nano models have a metal front and back. See images on this web page.

If you need assistance with placing an order, please visit an Apple Retail Store or an Apple Authorized Service Provider (AASP) and bring your iPod nano with you for serial number validation.

Your replacement iPod product is warranted to be free from defects for 90 days from the date of service.

There have already been reports that some devices are not eligible, which suggests that units manufactured by different suppliers do not suffer from the same battery issues as the units identified in the replacement program. If you are worried about whether your iPod is at risk from overheating, check this site and follow the instructions listed on the page.