Shower pump (feed?) issue/noise

[Plagueof1]

Hi

could someone help me identify the possible source of this issue.

we sometimes get a weird vibration sound when using the shower pump.
It’s very infrequent, we can go many showers without it happening, but then it’ll happen a few times in a row.
The shower doesn’t lose/gain any pressure/flow or any change in temp before, during and after the noise

The noise doesn’t sound like it’s conjng from where the pump is but above HWT slightly off to the side, towards the cold water feed for the pump.
Noise differs in volume and length at times.

I’ve attached a video/sound file of the noise.

also, bit if background to a previous issue that resolved by changing the showers thermostat.

Thermostat or shower pump prob + poss replacment - https://www.plumbersforums.net/threads/thermostat-or-shower-pump-prob-poss-replacment.104589/

 

[SimonG]

Have a look at inlet valve on cold water storage tank in loft.

 

[Plagueof1]

Have a look at inlet valve on cold water storage tank in loft.

Can certainly have a look. Would that cause such a noise only when the shower pump runs? Seems a strange i’d get that sort of noise from the CWS just filling up.