Very top buds drying out

Hi everyone,
Need yours advice and opinions. week 7 in flower. Growing under full spectrum LED'S on 600w room temperature 30-31C° RH 55% in coco medium. Recently noticed that few buds on the top of the branches drying out,what errors could cause this issue ?
Thank you in advance for your attention.
Pictures attached. Last picture of normal bud just in case.

That looks suspiciously like botrytis, i.e. budrot.
Try tugging on one of the sugar leaves of the bud in question; if it easily separates, it's rot.
I hope I'm wrong.

Looks like bud rot .

Unga Bunga said:

Looks like bud rot .

Click to expand...

What causes this problem ?

Most often it's humidity and not enough air movement .

Unga Bunga said:

Most often it's humidity and not enough air movement .

Click to expand...

Possible to fix it?

Even if you dont see any mold it can still be. Ill be damned if this the first time I seen it happen to someone else but if theyre literally drying out over night no visual fuzzy mold it may be what happened to me half the time lately.

Still need to discard it and anything it touched. Check the root ball when you can or at chop to see if it looks rotted out. Its the shittiest thing I never heard of till it happened to me. Fusarium wilt. What sucks is that good bud has a sign its undergoing infection and death.

When theyre discolored from deficiencies or light burn etc its ok but if this is hitting you fast within light cycles, maybe not now but at some point can.. Its now a sign of something to toss.

I tossed 4oz of a 8oz plant. It sucks. It can still be present and producing mycotoxins in the branch with the suddenly fading leaf. Its toxic. Id call it a salvage op amd salvage what you can if anything sounds like what Im describing.

I've noticed one like dry bud but unfortunately didn't paid to much attention. After a week I found another few and chopped off. So checked some other buds and found some more affected. Most of the buds looks fine and firm. I guess it was happening for some time and didn't spread very quickly.
Thanks for your response