DRM and music
 Audio CDs
In 2002, Bertelsmann (comprised of BMG, Arista and RCA) was the first corporation to use DRM on audio CDs. This was initially done on promotional CDs, but all CDs from these companies would eventually include at least some DRM.
However, these CDs could not be played on all devices that were intended to do so, including some car CD players. Many consumers could also no longer play CDs they had purchased on their computers. PCs running Microsoft Windows would sometimes even crash when attempting to play the CDs.
In 2005, Sony BMG’s DRM technology installed DRM software without notification or confirmation; among other things, the installed software included a rootkit. This created security vulnerabilities others could exploit, and when the nature of the DRM involved was made public, Sony recalled millions of CDs. Several class action lawsuits were filed, which were settled by agreements to provide affected consumers with a cash payout or album downloads free of DRM.
Sony’s DRM also actually failed to prevent copying. The software had to be renewed constantly to combat cracking, yet this never succeeded. While the Sony DRM technology created fundamental vulnerabilities in consumer’s computers, it could be trivially bypassed by holding down the « shift » key while inserting the CD, or by disabling the autorun feature. In addition, the audio could simply be played and re-recorded, completely bypassing all of the DRM.
By January 2007, EMI stopped publishing audio CDs with DRM, stating that « the costs of DRM do not measure up to the results. » EMI was the last publisher to do so; audio CDs containing DRM are no longer released by any major publishers.
Source : wikipedia