For the past six months or so, my iPod Classic (120GB, bought I think around January 2009?) has been freezing my iTunes every time it's plugged in, and it's getting worse over time, which means I'm now almost never able to add new music or podcasts or to delete accidental on-the-go playlists or anything, rendering my iPod not really useful.

So. I'll plug it in and iTunes will launch, but then I will get either:

-the spinning pinwheel of death and then I have to force quit (often after doing this, trying to reopen iTunes leads to the error message that the disk is locked or I don't have permission to open it)
-it will say verifying forever and then pinwheel
-it will work properly and I can click on, say, a new podcast to put on there and drag it over, but then it will freeze
-it will work properly and I can delete or add something, but then when I think, "Well, I better just eject now for fear of anything else going wrong," I will try to eject it and some other kind of freeze will happen.

Also, after all this, I can drag the iPod to my trash to eject it repeatedly, but it will either do nothing or the icon will look grey, but it won't eject, and then when I yank it out the computer yells at me for not telling it to eject.

I also notice that it makes click-y noises a lot and that whenever it does disconnect from my computer (like, after it registers that it has done so), it restarts itself in the same manner that it does when you click menu+select.

This happened for months on my Macbook (mid-2007) and still happens on my brand new (November 2012) Macbook Pro. It has happened on more than one version of iTunes. I have checked my software updates for the computer millions of times, so that has nothing to do with it.

I have never had automatic sync-ing, so that shouldn't be slowing things down.

Things I have tried that either don't work at all or only work a fraction of the time and then eventually lead to more freezing:

1. Different computer. 2. Different version of iTunes. 3. Repair Disk Permissions. 4. Restore to factory settings. 5. Different cord. 6. Disk mode.