Originally Posted by
Derailed
I have the same combination of head light, tail light and hub. I have not had this problem. However, I agree with your suspicion that you probably have a faulty connection between the head light and hub. Unless you see signs of damage along with wires, I'd start by redoing the connection to the plastic plug which connects to the hub.
I was going to do exactly that tonight and check for corrosion too. I have been riding the bike for several weeks recently with another wheel and the little connector piece hanging loose. Maybe the copper wires inside the connector have become fouled or something. I hope it is a simple fix because I really love this lighting setup.