Or, you can use this guide (source: http://boards.dingoonity.org/android-devices/new-fireware-release-for-jxd-s7300b-and-update-guide/msg59690/?topicseen#new) :
JXD has release a new fireware for JXD S7300B, the new version is "S7300B-01-V1.1-20130118", this fireware optimize the sensitivity of the buttons and joystick.
Press “POWER” button and “VOL+” button together under POWER OFF state, device would enter automatic upgrading interface. Device would enter system again automatically after upgrade successfully.
After upgrade, the version is "S7300B-01-V1.1-20130118".
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