One of my first wheelset builds was ordered as a build kit, and came with all of the spokes pre-dipped in what I believe was wheelsmith product. It was on so thick that I was unable to thread the nipples in place and I ended up cleaning all of the threads off and using oil instead. Never had trouble with those wheels. Some time ago, I was turned on to Locktite 222 (Purple) which is for very small fasteners (very low strength), and will supposedly re-bind a few times for adjustment if needed. I've been using that for a few years, and again, have had no issues with it.
In a few cases when friends bring in wheels that have problem spokes, I will remove nipples, clean spoke thread and apply the locktite to the NDS spokes, all around. It's worth a try, and as long as the product you use has a bit of holding strength, it will likely solve your problem.
-Jeremy