ID3 tags that look fine in iTunes are ungood on the iPod touch

Question

I've got 60,000-plus MP3 tracks, collected over a decade, that were encoded by a variety of apps on Macs and PCs. The tracks look OK in iTunes on a Mac, but on an iPod touch, many songs are missing artwork, and others display the lyrics in garbled "mojibake" characters.
If the garbling occurred in all the ID3 tags (Name, Artist, Album, etc.) of a track instead of just the lyrics tag, I'd simply reverse the unicode; but as it's not, the solution has to force the misbehaving ID3 tags/artwork to display correctly. I've tried selecting the problem songs and reassigning the ID3 tag, but iTunes can't or won't overwrite the bad tags.
What does work as a solution is toggling the ID3 tags off and on by selecting the bad tracks in iTunes, right-clicking and choosing "Convert ID3 Tags...", then assigning "None" as the ID3 tag version. Next step is to select "Convert ID3 Tags..." again, this time choosing v2.3 or v2.4 as the ID3 version. That does the trick every time, stripping away corruption in the ID3 tags and forcing the tracks to accept artwork. However, it also truncates tags longer than 30 characters, and deletes existing lyrics and artwork. That makes for a lot of cleanup editing.
Is there a way to make iTunes assign ID3 v2.3 to tracks so as to overwrite the corrupt tags without going through the steps I've outlined? If not, is there an app out there with the mojo to fix these corrupt files?

Answer 1

If the song is in iTunes, and it is in a playlist that you auto-sync your Touch to, then the only things that might cause this problem are:
1- Is this new song un-checked in iTunes? If your Touch is set to sync only checked items that would prevent it from syncing. If that's the case, just enable the checkmark next to the new song and re-sync.
2- Is this playlist a smart playlist that is forced to be limited in size? If so, there is a bug with the 3.1.x OS such that smart playlists that are limited in size will have different contents (and sorted differently) when you compare the playlist on iTunes vs. on the Touch. The solution in this case is to disable Live Updating in the smart playlist definition, then the two versions of the playlist will agree.
3- Is the new song tagged as "Skip when Shuffling"? If so, and if your Touch is in shuffle mode, then the song count in the playlist will not include songs that are designated to be skipped.
See if any of those three things are what is going on. If not, then perhaps you need to reset or restore your Touch, but I doubt that.