iTunes not playing some iTunes Match uploaded songs since Apple Music subscription

I believe this is happening since I subscribed to Apple Music. I have had an iTunes Match subscription for more than two years now. Never had a problem. However, now there are some songs that I uploaded to iTunes Match that I cannot stream in iTunes. It keeps loading forever and the songs never start. Even if I download them for offline listening, I cannot reproduce them, not with iTunes, neither with QuickTime player. Its like the downloaded files are corrupt. The strange things is that I have no problem in streaming these songs form iOS devices.

The only common patterns I have found among these songs is that they were all uploaded by me before Apple Music started, they have the "Uploaded" status, and the location is "iCloud". However, there are songs with these same characteristics that I can correctly play.

I'm really ****** off right now, as I need to download some of these songs and I have no backup. I always trusted blindly in Apple, so I saw no reason to keep a backup of them, even if some of them are really important for me. So please Apple, I need a fix for these asap.

Also, any suggestions from the community are welcome.

By the way, I'm using OS X El Capitan 10.11.1 and iTunes 12.3.1.23 on a late-2012 Mac mini.

Thnx,

Tomas