butane gas can help get a bit more life out of dying faders (alltho it leaves a residue) …. mby a tiny bit of wd40 depending if it’s a contact fader or not (alltho i’ve never tried this so be aware it might fuck it up totaly lol). Or just a plane air spray like what you use to clean out keyboards … alltho all that will do is get rid of dust rather then help the contacts connect properly if there’s rust etc. in there.