I would advice anyone who can wield a screw driver to save some cash and purchase a replacment fader. You can either just get the fader which will require some soldering or you can get the whole unit which is a few screws and a plug. You can purhase a multimeter for very little money these days and you can then adjust the unit to factory specs.
Like any open fader, after time an accumulation of dust, skin, cigarette ash(if you smoke), and other particles find their way into the housing. The wiper then has problems keeping in touch with the tracks which relates to erratic pitch control. Most of the time all that is needed is to clean the tracks and good blast of compressed air around the wiper to blow away the debris. Caig Products are a good solution for cleaning.
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