OK, this is what I did to downgrade my friend's iPod touch MC:
Make sure you have iTunes 9.2 and the firmware for
3.1.2. Version 3.1.3 WILL NOT WORK!
You have to edit your 'hosts' file so that Apple can "authorise" the downgrade. Go into Terminal and type:
Code:
sudo /Applications/TextEdit.app/Contents/MacOS/TextEdit /etc/hosts
You will be prompted for your password, but you won't see anything if you type. This is normal, just put it in and press enter. TextEdit will appear.
Above where it says 127.0.0.1 localhost, enter a new line and type:
Code:
74.208.105.171 gs.apple.com
so that now, it looks like this:
Code:
##
# Host Database
#
# localhost is used to configure the loopback interface
# when the system is booting. Do not change this entry.
##
74.208.105.171 gs.apple.com
127.0.0.1 localhost
255.255.255.255 broadcasthost
::1 localhost
fe80::1%lo0 localhost
(That space between the numbers and the letters is a TAB)
Now save and quit. You can quit Terminal as well.
(This net bit is taken from the pocketables forum:
http://forum.pocketables.net/showthread.php?t=566)
Your iPod touch should now be in DFU mode, iTunes will tell you that it's in recovery mode and must be restored to use it. This is good.
Alt-Click (or Shift-Click for Windows) the "Restore" button in iTunes, and navigate to the 3.1.2 firmware for your device. Click restore and it should now go and do it's thing.
Please, let me know if this works for you.