Anyone know how to uninstall reverse the firmware update ? plz help :(

I recently installed the firmware update via the program provided by scandisk. but this update has caused the sound to go very quiet.

Can anyone please tell me how to reverse the firmware update or reset to the factory firmware so I dont have this problem. I have trouble hearing this player as it is and now its so hard to hear anything. Yes I have fiddled with all the settings etc I could possibly use on this thing already.

Thankyou so much for this help.  I need my mp3 while im working away and with all the noise from the road and my van I really need the extra volume to hear anything at all. Seriously much love :smiley: