Japan is investigating a possible battery defect in the popular iPod Nano music player after reports that two overheated in Tokyo, scorching nearby paper and a woven straw mat.

The latest problem follows a similar ministry report in March about sparks shooting out of an iPod Nano.

The government has been working with Apple to investigate the cause, and a defect in the lithiuim-ion battery is suspected in all three cases, he said. The iPods began to overheat while they were being recharged, he said.

He declined to disclose the manufacturers of the batteries, and said it was unclear whether the same battery was being packaged in the product…

Yoshitsune said the two latest cases involved an iPod Nano, model number MA099, which singed nearby paper in August, and model MA005, which burned a Japanese traditional “tatami” mat, in January. Both players were twisted out of shape from the heat and became unusable, he said.

Here we go, again.