Hi we just purchased a 50yr old split bungalow. (1st time home buyers) we keep on hearing water dripping sound inside the wall of our upper level when we use our toilet or shower in the upper level. The dripping stops right when we turn off tap or when commode tank is filled with water. We are bit concern. Is this a major issue to call plumber?

First determine if it is supply line leaking or a drain line.
Pour about 3 or 4 gallons of water down the toilet. If you hear a the dripping sound then it is in the drain. Post back.