In a statement to The Loop, Apple has confirmed that some users have reported similar issues, and that it is working to identify and correct the cause.

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“In an extremely small number of cases users have reported that music files saved on their computer were removed without their permission,” Apple (AAPL) told the site. “We’re taking these reports seriously as we know how important music is to our customers and our teams are focused on identifying the cause. We have not been able to reproduce this issue, however, we’re releasing an update to iTunes early next week which includes additional safeguards. If a user experiences this issue they should contact AppleCare.”

Pinkstone has been getting mixed messages about whether the deletion was a design feature or a bug. An Apple support rep first explained to him that users can authorize Apple Music to delete their local music files when it determines that a copy already exists in the Apple Music database. An Apple technician later contacted him and told him this was not true, and that the deletion was likely a bug.

Apple’s reference to “additional safeguards” hints that some users may simply be unwittingly activating an option to upload their libraries to the cloud, and that the update will make that choice clearer.

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While storing a personal music collection remotely is attractive to some users, Pinkstone’s experience highlights several problems with the idea, particularly for truly dedicated music fans. He says rare and unique files, such as song demos, were misidentified as later versions of songs, then deleted. He also says Apple Music downcoded his hi-definition WAV files to MP3 before deleting the originals from his hard drive.

Pinkstone also points to the larger issues his experience highlights: In the digital age, ownership of media is a very fragile thing.

Luckily, Pinkstone was smart enough to have a local backup of his files.