Orange Speckles Please Help! (Not heat stress)

I'm about a month into flowering and I'm seeing this problem mostly on one single plant but one other plant which is much healthier is showing a little bit of the same spots. I don't think it's caused by heat stress since these are lower fan leaves. I'll let the pics say the rest. Any help on what the problem is and what to do will be greatly appreciated.





This is the healthy plant, took the pic under hps light because I didn't want to cut a leaf off.

I'm sort of having the same problem. I have 1 plant that's 3 weeks old and is developing very small spots like this. Would like to see if anyone knows what it can be.