I've tried a 4GB micro SCHC card and it did fine. However, after about a week, the unit quit keeping a charge. When I charge it, it will say it is full. But, when not connected to the PC via USB, it shows low battery and and will not play. It seems to be going downhill. I player will now only work connected to the PC. Virtually useless now, since I can do the same thing on my PC.
