Erased music

Hello!

I own a IPod classic 160GB.

I Had more than 80GB of music and have always used my IPod normally.

Last week I was inserting new music, but it didn't work, so I ejected my IPod I forgot about the issue.

Yesterday when I tried to use my IPod it froze and rebooted by itself. When the IPod started working again it didon't have any music!!!!

My friend has an IPod Touch and the same thing happened to her.

Do you guus know if there is a problem with the ITunes syncing? What it's going on?

Help!!!!!