Troubles syncing podcasts on iTunes

Hello!

i don't know if someone had experienced with.

When i sync the podcasts in iTunes, the settings of a couple of podcasts are modified, if they aren't deleted from my iPhone.

For example, it unsubscribe me from the podcast and i have to reset it. Sometimes the podcasts are simply deleted from the iPhone. And they appear in double in iTunes.

PS: i also have an iPod touch 4th gen that i use on the same itunes library.