ipod shuffles turning off randomly (2 separate ones!)

This is really bizarre. I have had an Ipod shuffle for about a year and a half. All of a suddent it starts shutting down at random
times, even though charged. Sometimes takes 5 minutes or longer to turn on again. so figuring it was bad I bought another new one

yesterday. Same problem occured!!! 2 different shuffles, two different sets of headphones. Both restored through Itunes.

The only commonality seems to be the software and the itunes library. Could a corrupt song file create this issue. I can find no other

commonality between 2 shuffles born a year and a half apart.