However, you have two options to still listen to these files.
...In addition to preventing anonymity in access to digital information, DRM can be used to facilitate profiling of users' preferences or to limit access to certain content. This is done by assigning an identifier to content or to the content player, and attaching personal information to the identifier. For instance, Microsoft's Windows Media Player has an embedded globally-unique identifier (GUID) to track users...
...Windows Media Player creates a log file of the content a user views, and "phones home" to a central server to obtain content titles. These technologies mark an important development in the use of copyright law: copyright can regulate duplication of works to protect content owners. Now, copyright is being used as a justification to both protect content and to profile the consumers of content...
... Proprietary software means, fundamentally, that you don't control what it does; you can't study the source code, or change it. It's not surprising that clever businessmen find ways to use their control to put you at a disadvantage. Microsoft has done this several times: one version of Windows was designed to report to Microsoft all the software on your hard disk; a recent "security" upgrade in Windows Media Player required users to agree to new restrictions...