Water Softener shooting water.
Unless the leak only happens when the softener is in a regeneration, it sounds as if you are on city water and the pressure increases when your water heater comes on or the city was sending too much pressure. If you have an expansion tank at the water heater it may be bad or... Or your pressure regulating valve is not working right or you don't have one and need one.
Exactly where on the softener was it leaking?
23 years in water treatment and well pumps, 13 years on the 'net helping others to help themselves.