Out of about 10,000 downloaded matched tracks, I found about 40 that were corrupted in some way or another. "Get Info" identifies them as MPEG files, not Matched AAC.
I can add to your list once I get home from work. Somehow I managed to create a playlist that can detect the corrupt files. If a subsequent redownload grabs a good file, the track disappears off the list.
Here's one I can give you right now:
Morganspaziergang - Kraftwerk - Autobahn
The question that needs to be asked and confirmed here is were these tracks actually matched and replaced on your machine? Or were they your own tracks that got uploaded. If they were your own tracks that got uploaded it is possible that they got corrupted when they were uploaded. If that is the case you should be able to completely delete the tracks from itunes, and itunes match, then restore them to itunes from a backup and let itunes reupload them. If they are in fact matched tracks and your original file has been deleted from your computer, and replaced with the matched track from apple, then they should be confirmed and reported to apple. I can say that I have matched and downloaded Lullaby by The Cure, and the version I downloaded from itunes works perfectly.
These were matched tracks. I even used the playlist trick from MacWorld to make sure the list I was downloading from was a "matched" or "purchased" track. When I would do a mass download of Matched AAC tracks, the file would disappear from the Matched playlist, show up in the "corrupt" playlist, then disappear from that list if the file checked out.
I will periodically go back and attempt a redownload of the corrupt files. Little by little the list shrinks a couple of files at a time.
Like I said, I've only had ~40 bad out of ~10,000, so the percentage of bad files is incredibly small.
Yep, they were "Matched" files, as opposed to "Uploaded." They all show as 256 kbps, which isn't a bit rate that I normally import at. Basically I also did a mass delete/download of all my songs that could be upgraded (ie 256 kbps, iTunes Matched).
I would try to reburn copies from my CDs and re-match, but I don't have them with me at the moment.
I have this exact issue, and the list of songs that won't transfer to my iPhone or play in iTunes actually grew after a couple days (was just a mix of Joanna Newsom songs, and now a few Radiohead are thrown in). The songs were matched, but can't play in iTunes. I deleted them from iTunes (not iCloud) and re-downloaded them from iCloud, but no go. The iCloud synced versions will play on my iPhone without a problem. Very strange.
I submitted the issue to the Express Lane, and the reply was:
"When using iTunes Match and switching the files to be used in iTunes, some purchases may have already been corrupted and are unable to be used based on the third party site that was used." and a link about iTunes Match status icons. >.<
Here's a partial listing of corrupt files I've found. Repeated deletions and redownloads have no effect.
Full of Fire - Al Green
Mr. Moonlight - The Beatles
It Won't Be Long - The Beatles
Inwards - Big Country
Chance - Big Country
The Storm - Big Country
Hard Headed Woman - Cat Stevens
The Makings of You - Curtis Mayfield
Jump Study - Dr. John
Angelina - Herb Aplert
Little Girl Blue - Janis Joplin
Up From the Skies - Jimi Hendrix
Ladies Room (live) - KISS
My Little Red Book - Love
Time Has Told Me - Nick Drake
Jägerspiel - Laibach
I had a smart playlist with these settings:
Bitrate is 256 kbps
Media kind is Music
Kind contains MPEG
iCloud status is either Matched or Purchased
I'd used the playlist to find 256 kbps mp3 files, but then I noticed some of the tracks didn't leave the list after downloading. And they wouldn't play.
I also discovered that when upgrading the lower bitrate tracks, they would show up in this new playlist while the download was pending, then disappear once the file checked out as good.
Still holding at 39 bad tracks out of over 10,000. good percentage-wise, but of course some of those 39 are tracks I like to listen to.
Change the extension from .m4a to mp3 and they will most likely work. I've ran into several like this as well. This isn't a fix for the fact that Apple has the file type set on the files or the fact that Apple is sending out mp3's instead of m4a, but you can at least play the songs until they fix it on their end.