Does this happen to some of you? Do mushrooms need to be cooked a bit longer? Do you bake for longer or dome for longer if you are using mushrooms or an ingredient that simply takes longer?
I think you either go longer or shorter. I think there is a "wet zone" for mushrooms. I often use fresh mushrooms on NP, but I'm typically in the 45-55 second range. They soften and start to cook, but the haven't done the full water release yet. The problem is that if you want to go longer, you will need to lower your bake temp which may change the character of your pizza.
Another thing you can try is slicing and pre-baking the mushrooms to drive off some of the water. Put some evoo on the pan so they don't stick. Doing it this way as opposed to sauteeing will help preserve some of the earthiness of the mushrooms. I make a couple different pies with the mushrooms treated this way, it it works really well. Roasting them with a bit of pepper and thyme works well too.
I've never tried it, but might be able to accomplish the same thing and retain all the earthiness by salting the mushrooms and draining them on paper towels.