I have a sewage pump unit in my basement, I have a toilet that sits directly on top of it, and a vanity sink tied into it. When the pump runs it seems to be starved for air. i.e. sucks the p trap dry so I always run water in it to to fill it back up. My question is if the toilet gets a lot of use in one night, I have a stale urine smell that shows up, and is highly intolerable, It seems to me as though the urine smell is being forced out between the toilet and the wax ring, I am not sure. This entire unit is vented with my septic stack, does this unit need its own vent, and is the unit starving for air and forcing the smell back into my house? Please help, the smell is nauseating to take care of when it happens.

Yes, it must be individually vented