Lower branch problems- dying leaves and discoloration

Hello friends,

i'm having problems diagnosing my ladyplant's problems.

strain raspberry cough
using cfl's 2x 4000K 60w, 2x 2700K 32w and 3x 2700k 23w
temps 75F day/ 69night
humidity arround 44% ( durring night i guess it spikes up to 65%)
she has been flowering for 4 weeks now
medium storebought potting soil +extra perlite +extra vermiculite
i feed her complex nutrients npk 2-6-6 +micro and water with ph balanced water

the main cola at the top looks great but recently i noticed that lower branches especially the budsites, are showing some health problems. the're turning bright green, the tips of the leaves die off and there's almost no flowering going on on these branches.

and some of her large fan leaves are showing some weird discoloration, and eventualy they just drop off. by the looks of it i think it might be P deficiency, might this be causing the lower branch problems aswell?

Your problem could be many things, but if all of this "bad stuff" is near the bottom of the plant, I'd not worry too much because your buds look spot on. However, your plants look "thirsty". And by that I mean, they look like they are burning up. How hot is your grow space? How close are your lights to your plants? Are you over-nuting them? It's a weird combination to see such nice buds but bad things happening under the canopy. Maybe someone else can chime in, I'm a little stumped.

I see alot of bad things...
Leaf tips curled up
Leaf tips curled under.
Leaf Margins dead
Leaf Margins curled up
Leaf purple spotting.

I'd check my pH first, and go from there.
Your fan leaves will take a death dive a little later in flower, but your not that far into flower. You should be having all these problems.

Sure does not look healthy, i'd get rid of all the infected areas. Are you or have you been foliar feeding? Your humidity should be lowered + get her more light. How's your air flow? What's your watering schedule and what size pots is she in.