The 1600 error in iTunes is caused by already upgrading to 3.1 firmware. If you do this and then try to upgrade to a custom 3.1 firmware. iTunes knows that it has been modified and will not let you install. Luckly you can delete this file and ...

In iTunes you can only create a ringtone from a song if you have bought it from iTunes. If you try to convert it you wil get the error message "A ringtone cannot be created from the following file, You can create iPhone ringtones only from son...