Low Dynamic Water Pressure

Lukesavage

I have static mains pressure of over 5 bar reduced to 3 bar by a pressure regulator. In the past the dynamic pressure has been steady at 3 bar with several sources drawing water at the same time (eg a shower, a tap and a toilet). Recently the dynamic pressure has fallen so that you notice a significant drop in flow with anything more than one source drawing water. I replaced the regulator but that has made no difference so I’m assuming it is a partial blockage upstream - eg. the water meter sticking and slowing down the flow. Does anyone have any similar experience or ideas on how to locate the problem?