Looks like salting to me too. There's both burn and def symptoms on the same plant.
How much runoff do you get when your nute delivery system is going? In terms of, every time you water, what is the ratio of water in to water running off?
For example, when you are running drip-to-waste, a 10% runoff acts as a constant flush so that anything not used by the plant is constantly being washed out of the medium.
Practically applied, If you pour in a gallon, and nothing comes out (=it is just enough to feed the plant and not flush it), anything that was not used then gets to sit in the medium and possibly react/recombine into molecular substances you DON'T want.
Just a couple ideas to think about.