I can tell you that using Xerox paper will not fix your problem. Xerox reps and so called specialists love the easy way out. we were using xeroxs own 140gsm brand and it jammed all day long
its not the paper brand causing the jam really...its the moisture levels, all which can be effected by your environment, how its warehoused at supplier, etc. your problem is your getting moisture in the sheet and static as well and they sticking to each other. fanning them heavily before going into tray will stop problem but if there is any weight of paper in the stack then by time machine gets to bottom sheet they have stuck to each other again
plus as I have mentioned roller wear and tear...dirt and dust lying on roller all cause jams...xerox have this magic fluid for cleaning rollers and whilst it fixes it for a few hundred sheets once it dries off it returns...i managed to get 2 bottles of this "Enginner only" magic fluid but after getting bored with it the only true fix is HCF