After a recent house move I got a Home Hub 5 so they didn't need to install a seperate VDSL modem and due to the layout of this place it's on the desk with my PC. When it's downloading data (and download only, not upload or anything else) it makes a low but noticeable buzzing/hissing noise, think like the noise you can hear when a hard drive is being accessed that sort of thing (obviously that's mechanical noise and this isn't though). It's annoying as hell, tried different plug sockets to no avail so thought I'd see if anyone else experiences the same before I start banging my head against the wall trying to explain it to BT to get a replacement or something.
I can hear my HH5 make a low level static type noise,(It is very quiet though) when I use a speedtester over a wifi connection but not when downloading via wire.
Also it does not consistently make that noise every time.
I have tried a few times downloading large and small files since reading your post.
For me I think my HH5 is fine, I have to be right next to it to even hear it.
I hope you find this information useful.
Interesting, I'll give wired a go - it's only really noticable when I'm downloading the big stuff on the PC it's sat next to anyway, which is only wirelessly connected as I changed the SSID and pasword after install and it just picked it up automatically. Also I've just realised I've got BT Sport on in the next room running wired via powerline and I can't hear anything from the box so maybe that's the ticket, thanks.
Assuming here we are talking about audible noise.
The HH5 has some switchmode regulators inside that use inductors (coils wrapped round ferrite material, somewhat similar to voice coils found in speakers). There are several for the different power rails and the switchmode power supply changes frequency depending on the current being drawn on the power rail and the hub will draw different amounts of power depending on what it is doing, hence the change in frequency and amplitude that you hear depending on how busy the hub is (the more current through a wire the more it or the ferrite former will move and the greater the amplitude of the noise).
Not sure replacing the hub will fix the issue unless they start putting silicone gloop on the inductors to damp the vibration but from what Nige32 says it may only be the power rails supplying the WiFi transmitters that have the noise issue.
I'm getting this too. It's quiet but noticable when the room is quiet, it's pretty annoying.
It would seem though that it's not a faulty unit if everyone is getting it, so I guess I'll have to put up with it 😞