WMA from OverDrive can be stripped DRM easily if u read some topics in this 4rum. Today, I removed successfully DRM from WMA file .
So, there all 2 freeware tools I used to remove:
- drmdbg 20090303: to extract key from wma files
- freeme2: to remove DRM
And remember you must put the wma files, the key file in FreeMe2 folder. Now, I can play wma files on other players

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Some topics that I read:
HowTo Instructions for Removing DRM with drmdbg & FreeMe2 (from Windows Media Player)
freeme2 - free software to remove DRM protection from Windows Media WMA,WMV,ASF files
Good luck to u

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