Are there any suggestions as to how I can clean/lubricate plastic slide controls running in a plastic channel? I'm sure there is a build up of dirt, dust, grime, etc in the channel causing most of the slide controls to stick. I've tried Windex, 3-in-one oil, white grease and silicon, cleaning best I can after trying each one. It works to a degree but they still stick. Problem is I can't get at the sliders from the back because a circuit board is glued on right there. Otherwise I would flush the thing out with soap and water. Thanks for any suggestions you may have.