Synapse 3 Erro?

I recently bought a Black Widow Elite keyboard and noticed that when I use the side 2 buttons on my mouse (linked to R & CTRL) my A key stops working. Basically if I'm crouch-walking in FPS games I cant walk to the left. If I release CTRL my A key works perfectly fine but once pressing CTRL my A doesn't do anything while W/S/D still work fine. Any ideas on why this could be happening? I thought it was just a faulty keyboard and returned one but the second one is still doing it as well.