I'vebeen experiencing this issue some time ago, and I followed this discussion to understand what could be the solution.
Then I tried some ways you already explained before with non results.
I had problems with chopping off songs on iPhone and iPad on iTunes Match, while on my MacBook Air everything was right (the library is physically stored on the Mac, instead of my iDevices that access to it only with iTunes Match).
The songs that reported the issue were mostly the ones "matched" to the ones present in the iTunes Store. To sum up, when we match a song, on our computer we keep to play our version, while the other devices stream the Store version.
I went to the Genius Bar in an Apple store nearby, they tried to access my iTunes Match library from a brand new device and it reported the same problems I had with my iPhone and iPad. So they suggested me to contact Apple Care by phone. No solution arrived from them. They told me to try some workarounds I already had practised by myself, with evident no result.
Then I got an idea (by myself, not suggested by Apple): for the tracks who had the reproduction issue, I removed my version from the library on the Mac, downloaded the iTunes Store version, then copied it out of iTunes, then I erased the track also from iTunes Match. After that, re-adding the track previously saved somwhere else from iTunes in the library (this time the AAC file coming form the store), updating iTunes Match makes all work good. No more chopping off tracks.
The negtive aspects of this procedure are:
- you have to know exaclty which tracks have the mentioned issue
- the procedure is not so quick if you have many tracks to fix
- with this procedure, you lose all data on your tracks (reproduction counter, classification, etc) and your track will disappear from any playlist (maybe smart playllist will add them again as you re-import the tracks, but it depends on the smart criteria of each playlist
At the moment, I didn't find any other way to fix the problems. This solution is not the best ever, I suppose, but it works.
I also think that Apple will never give us an official fix for this. I felt that during my multiple phone calls with Apple Care service, and I'm pretty sure it will be so.
Anyway, I hope to have been useful for you all, if you want to try. Obviously this fix works only on matched songs and not on the uploaded ones.