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Router vs telephones?

Community Veteran
Posts: 1,371
Thanks: 33
Registered: 07-03-2008

Router vs telephones?

Hi Folks!


Noting that some of the posts seem to be concerned with these devices, I have noticed that my TP-Link W8968 seems to be causing a mains frequency hum to be heard when I pick up any of our phones which is there when I dial a number or not. We have only one phone number and only one ADSL connection. All the phones are via proper filters and are dotted around the place. This hum used to be not so audible but it is irritating and I want to do something about it. I have tried limiting the number of phones connected to one at various locations without any improvement. The router does what it should do with no changes there and, if I switch it off, the hum remains. Any one got this trouble and located why it happens?

Community Veteran
Posts: 5,116
Thanks: 1,225
Fixes: 30
Registered: 16-10-2014

Re: Router vs telephones?

@colintivy - If the hum remains after turning off the router then it's not the source. I'd look closer to home like a fridge / freezer. If you can unplug all devices in the house, everything, including chargers. Then one at a time turn them on, until you find a source. It may even be the PSU on your PC that's causing the issue.

If you find one that introduces the hum then turn off everything else you turned on before and try it on its own to confirm it is the source. Armed with that you can then decided what you need to do next.

Posts: 603
Thanks: 106
Fixes: 5
Registered: 28-02-2017

Re: Router vs telephones?

Power down your router and then carefully remove the face plate from the master socket.


Plug a phone into the test socket now exposed. Noise equals a possible fault on your line. No noise means the problems within your house.



Seasoned Pro
Posts: 10,705
Thanks: 218
Fixes: 9
Registered: 01-09-2007

Re: Router vs telephones?

Whilst you are at it, do a quiet line test by dialling 17070, option 2. You should have zero noise.

Posts: 2,883
Thanks: 1,222
Fixes: 9
Registered: 10-04-2007

Re: Router vs telephones?

Remember to switch the Router 'Off' at the mains socket and not just at the Router On / Off switch!  I've seen  a few cases where the external power supply is at fault in one case totally swamping the ADSL signal.