This flash memory-based player is the de facto successor[3] of the ZEN Vision:M and was announced on August 29, 2007, to be available in capacities of 2, 4, 8, and 16 GB, as of September 14.

[4] A 32 GB model was announced on December 4, 2007, setting a record for storage capacity among flash players.

This is considered poor by some reviewers expecting the SD card to function as an expansion of the internal storage.

Though an Import All command makes copies of SD card tracks to internal memory, it fails to index them (even after Clean Up) hence leaving them completely inaccessible.

The earlier versions have reportedly caused players to occasionally result in a white screen of death.

This variant appeared following an EU Commission proposal to address hearing health concerns by requiring a limit on music player output level.

[14] The latest version of Nero-AAC Encoder (1.3.3.0) "solved compatibility issues with some hardware devices", including ZEN.

The form factor is similar to the ZEN's, being slightly less than a millimeter thicker at 11.9 mm (0.47 inches).

[16] The ZEN MX features the MSC/UMS transfer system that makes the player compatible with Apple computers.