Thanks for your reply, When I use the stock Pisen battery supplied by Ibasso, it shows the charging icon on the screen until it is fully charged and then the icon changes to a solid green ball. It doesn't do this with the OEM Samsung battery. Im referring to charging with the device switched off.

Hi sorry for late reply,  I ended up having the dx50 replaced under warranty and have since bought a dx90. Many thanks for your reply though.

I've recently changed to the OEM Samsung battery on my DX90, it does seem to have extended the run time a little but one puzzling glitch is that the battery charge indicator never stops indicating that charging is taking place when its plugged into mains charger! Any ideas?

I formatted myDx50 and ended up having it replaced under warranty. If the internal memory shows zero you have the same problem I'm afraid.

Thank you for your reply.  I just see  'e' and 'f' drives now so I guess the device drivers have gone! The DX50 screen does not show usb hook-up either. Is there any way of reloading them? 

thank you I think I will have to do that.

Can anyone help please. i think i may have accidentally formatted my dx50 whilst formatting a new micro sd card! My computor just sees the player as an empty E drive now and i cant send new firmware to it. any ideas please?