noise coming from water manifold

[JMR7738]

Have a 2006 cambridge fifth wheel CA 308RL 506 and I am get a weird noise coming from the water manifold. It sound like something is stuck and blocking the water flow.
does anyone know of this type of problem and how to fix it?

JMR7738

[wa8yxm]

Would need to hear it but something is.. sort of.. blocking the water flow, A spring loaded valve. at LOW flow rates it can make noise (City water connection)

On some RVs there is also an inlet pressure regulator and they make noise. Same as the check valve but louder.