Why is every thing erased from my iPod??

Which version of iTunes are you using?

And what is your iPod firmware number?

Only one of the Mackbook Pro USB ports is iPod Compatible, the rest are using shared resources with other I/O devices like iSight, Bluetooth, Infra-Red, so when you do the iPod Sync, connect it to that High Power USB2.0 port. Unfortunately I can't tell you which one, as there are a few variation of MBP, USB port, you have to figure out which port is good for syncing, and which one always freezes your MBP.

When it freezes on you, disconnect it by doing a iPod Hard Reset, as sometimes, you can't shutdown the MBP, as it freezes, waiting for the USB Host Controller acknowledgement trigger.

Do not disconnect the iPod, if you see the "Do Not disconnect" screen on the iPod, so better do a Hard Reset.

Have a nice day!

So your software and firmware are uptodate, the problem would be iTtunes 10.5.3 doesn't handle slow devices like iPod Classic very well, so if the iPod data transfer signal is slow, iTunes may terminate the data transfer and reformat(resrtore) your iPod, to clear any corupted filesystem flags.

As for the USB Ports, you have to try, one at a time, if both are on the left, I think the one nearer to the screen.

Do a Disk Diagnostic on your iPod Hardisk, read this post by tt2,

https://discussions.apple.com/thread/3110831?tstart=240

If the Realloc and Pending numbers are high, sent it back to Apple, as you just bought it..

Good Luck!

Have you left the iPod in the oven or on the car hood, the Temperature is 254C, which would have fried some bacon, hence the high pending and realloc numbers, these number can be misleading.

So better bring in your iPod Hardisk for replacement, there is nothing the community can suggest, to fix the iPod Hardisk.

Have a nice day!

Yeah, bring it to Apple store, they might replace it if under warranty, or else they will ask you to get another for about $100, as some other users has experience.

Hopefully they replace it for free, just put on your best grammar school behaviour, with a nice PussNBoots eyes.

Good luck!😀