Hi, I had a problem with the mouse in two places. The black wire going from the small pcb inside the mouse out was loose - in fact the solder appeared to have degraded and the metal of the lead corroded by something. I also found a similar bad connection at the microswitch under the mouse button - but you have to dismantle the mouse totally and re-solder both connections. The swg of the wire used by vtech is not appropriate for a children's device. Anyway, thanks for leading me in the right direction!
Thomas McCloughlin, October 2009