I have two sinks in my basement. Each of them are plumbed into separate pumps which send waste into the homes main drain. The hallway kitchenette sink is connected to its own pump located in the adjacent closet. That closet smells HORRIBLE and is actually causing the entire basement to stink. Across the hallway I have a restroom. The fixtures in that restroom are connected to their own, larger, submersed pump in another closet. When you turn on the water to the hallway kitchenette sink you hear the pump turn on as it’s working, but then, within a minute or less, the restroom sink across the hall turns into a geyser and some very foul smelling water is being splashed out onto the floor/wall. The water quickly drains from that sink with no further issue once you turn the kitchenette sink off across the hall. No other sinks/showers in the house seem to be affected. I can run the restroom sink and shower as long as I want with no issues at all. The geyser only occurs in the restroom sink (not shower) when you turn the kitchenette sink across the hallway on. Any thoughts or suggestions? I made a video and took photos to try and attach to this post but I cannot figure out how I get that feature to work.