Pressure relief valve

Good morning,

First post!

My question is about the water relief valve where my main water line enters the house from the street. Lately, I have been hearing some "whooshing" sounds when the toilet is flushed and filling back up as well as when the washing machine is filling up.

Lines are PVC pipe. Is it time to replace it or is there a filter possibly getting clogged and can be cleaned out?

Thanks

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