I have just upgraded from MM3 to MM4. I have an iPod Touch 2nd Gen (software version 4.2.1) and iTunes 10.6.1.7
Having synced just one album through MM I went back to iTunes to sync Calendar and iTunes says it can't read the database on the device and I need to restore it. I've restored it and tried again and exactley the same thing has happened. What is MM doing to my iPod?!
I've gone through the iPod Sync Guide on the MM Wiki but some of the Device Configuration options are (out of date?) different in MM4. I specifically can't find the "Force i-Tunes Style Folders" and I wondered if this is the root of the problem?
The really irritating thing is that I upgraded from MM3 to 4 this morning becasue MM3 had stopped detecting the device. MM4 has solved that but created an even bigger problem and I seem to have lost all my playlists in the process of upgrading...grrrrrrrrrrrrrrrr