Walkman fans have been wishing for Sony to add expandable storage to the Walkman for ages. Ever since the A810 series, users were wondering why the lack of support for micro-sd. This went on for several generations and varying series' of Walkmans. Of course one of the main reasons was that Sony would be able to release higher capacity versions at inflated prices. The arrival of the ZX1 ushered in an era of higher capacity for the Walkman, but it came with a much higher price. Still there was no expandable storage on a device designed for high resolution audio files which take up a lot of space.