I had this happen. Ended up being a loose fitting behind the shower wall. Came straight from Thor that way. Dealer used a camera and found it dripping down onto the floor and out from under the seam of that removable panel. They had to take the shower out tighten and put back in. Was a lot of back and forth about how it wasn’t leaking until they eventually agreed with me and found it. Almost every fitting in the rv was loose enough to leak from the factory..
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