And we’re not talking about “hot sales” either.Japan is investigating a possible defect in Apple Inc.’s iPod after one of the popular digital music players reportedly shot out sparks while recharging, a government official said Wednesday.An official at the trade and economy ministry, which oversees product problems, said a defect is suspected in the lithium-ion battery in the iPod Nano, model number MA099J/A. He spoke on customary condition of anonymity, saying he is reiterating a ministry position.The problem