Sync button no longer working, can i fix it?

Hello there folks.

I've been using my controller via a bluetooth connection at the pc for a couple weeks now, today i decided to connect it with the cable, since the battery was dying. Ever since then the controller's sync button no longer works and i can't wireless connect it anymore.

When i press the power button followed by sinc it still gives quick blinks, but doesn't connect, nor does the sync button work on it's own. How can i fix this, what in the seven hells is going on?

Please help.

:)