With those buds on them it should be developing a smell.
You got a bit of nute burn going on there and it's worse near the tops because it's hotter up there so more water and the salts from the nutes are going to those leaves. The water gets evaporated to cool those leaves but the salts get left behind and burn the leaves. It will likely get worse as time goes on.
The curling up of the leaves edges is an indicator of heat stress. Radiant heat from lights can really warm up the tops.
You don't mention how they are grown and what they are fed or the levels of feed. Handy info to have when trying to figure out what's wrong with someone's plants tho your problem is pretty evident.
They are looking to be about 5 weeks into flower? I'd not feed them anything for a couple waterings at least if so as they need less feed late in flowering and cut out nitrogen completely if you can. They seem to have plenty of that already going by how green the lower leaves are this late in flowering.
Good luck!