You can try a full reset see if this resolves your issue.

Let the Antminer S3 powered up and running for about 3 minutes, then use a paper clip or something thin to press a button inside this hole on the "RIGHT" hand side of the Ethernet cable connector.  Press and Hold the Button for about 10 seconds, Then, wait for 3 minutes, then Press the Reset Button 1 more time and release .   wait for 3 minutes, then turn the power off and power it back on.

You can also try flash the files again but remove the checkbox "keep the settings" this will make sure there are no wrong setting saved in the antminer,.