No sweat....
Not sure where you're at, but little microscopes like these are easy to find, cheap & can help you out when sussing er out.
https://www.amazon.ca/Active-AEM100-Microscope-100x-Magnification/dp/B004ATVHB8
I've had similar problems on balconies. They can come from anywhere really.
Neem Oil with finely grated garlic and R/O water (or ph'd 6.5-7 dechlorinated water) should do. Begins to smell like funky garlic cheese strains after it ferments a little. I kind of like it although it's a bit offensive.
Flush hard 2 weeks out, allow to dry out completely (buds will get airy and foxtail when the soil is always wet), Flush hard again 1 week out & allow to dry out completely watering only enough as needed. Best allowed to dry out in-between flushes to ensure roots get enough oxygen and buds don't...
It's looking like that should do the trick. Remove any potential host plants and give the area a good thorough clean. Apply the foliar every other night till you have it under control and then maybe 1-2 / week till flower. Make sure to spray the soil as well as they can lay their eggs there...
Looks like the beginning of a little russet mite damage & Magnesium Def. I would spray with neem & garlic water along with a little Epsom salts. If that's the problem of course. Any pics of the leaf undersides?
Organic all the way! They're just happier, healthier & stronger plants when your soil is alive & well with no salt build ups. You will notice 100% once you've got the soil microbiology down pat.