Noisy toilet refill

[BazzaS]

I recently fitted a new syphon and new inlet pipe/valve (bottom fill) to my toilet.
Since then, the noise of water rushing through the pipes has increased, when the toilet refills, over the noise level before.
The syphon and inlet are standard - i.e. from B&Q.
The inlet valve has a 'silencer tube'.
I've not changed the water pressure.
The noise appears to come from the pipes rather than the toilet itself and is a 'scream-like' sound.
There's no 'whooshing' or 'clanking' on refill.
Hope this is clear - from a layman.
Can anyone advise what has caused this and how it may be fixed.
Thanks

 

[crockett]

You didn't say whether the wc was connected to the mains or not. If so, then sometimes a restrictor fitted into the inlet valve can quieten the noise, by reducing the rate of flow. Did your B & Q cistern come with a separate fittings kit ? Normally these kits come supplied with an inline restrictor.

 

[BazzaS]

Thanks...
Yes the toilet is connected to the mains.
If the inlet came with a fittings kit it has been 'tidied' up by she who must be dismayed.
I notice that in the valve itself there's a 'trumpet' shaped piece - narrow end at inlet, flared end towards the float - is it this that should be replaced with something ?
Regards