for the potentiometer change the lamp must be removed (very easy) tighten the screw of the potentiometer by sticking it with super glue and expand its passage on the rear casing (the small rectangle) .the malfunction potentiometer holds in that it rubs on the frame of the lamp which loosens the potentiometer.
Independence I bought a Sony NP-FH50 battery very high capacity (over 2900 mAh) (in AboutBatteries) with Sony magazine (take care Patona brand ... Now it is nickel and very little fonctionnel.Un better than chinois.enfin for the price if you make these changes is a good handyman produit.faut be good and very thorough. great product