My Monstera has pale specks on the leaves. I noticed it on one leaf first, and it's slowly spread to others. I have also noticed tiny black specks, about the size of a grain of sand, that I think may be bugs.
I treated the plant with neem oil yesterday (the shiny patches) but I'm not really sure what the pest is, or if it could be somehow related to watering. The plant is mostly kept indoors, watered about once a week.
I've read a few articles about common Monstera pests but nothing I've found has quite matched the symptoms.