Cold water storage tank noisy when filling

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This was mega loud when it had an old float valve in it. I replaced it with a fluidmaster side entry valve which when I was in the loft was impressively quiet. However, when I'm in my bedroom which is next to the airing cupboard it still sounds really loud when filling. Kind of like a whooshing noise.

Ive tried turning the stopcock fully open and the open just enough to give maximum flow on the taps but this didn't help.

Its so annoying is there anything i can do?

Thanks