In reply to a post by pspr33:

I've just done a quiet line test without the router turned on, line was deadly silent. I turned the router on and lots of noise, crackles and whistling occurred. I moved the router into another room and tried again, same thing. I disconnected the router and the noise went away. My question is, why does this happen, why has it only just started to happen and why does it happen at certain times?

As a first shot, I think I'd be having uncharitable thoughts about the router power supply... have you one from another piece of kit (same voltage and polarity, at least the same current rating) that you could try?

your noises are audible noise being generated in response to the ADSL frequencies. This could be a filtering problem - unplug everything else from the system and see if it's still there. If it is then try again in the NTE5 test socket with a known good filter and phone to listen in.

Microfilters do fail.

If it's present in the test socket it may be a line fault, see if keeping the phone off-hook affects the speed it connects at.

In reply to a post by yarwell:

Microfilters do fail.

Wouldn't a failed filter tend to show up as some sort of hiss (or other fairly steady noise) on the line, rather than snap, crackle and pop?

That's why my first suspicion went for the power supply, they fail too. Rather more often, ime

I've got 3 filters, one of them brand new fitted yesterday. I can't see 3 of them being faulty.

I've turned all of the MCB switches off leaving only the sockets turned on, still noise on the line.

When I disconnect the RJ11 connected to the router from the filter, the noise stops. When I reconnect, there's noise.

This also happens with both routers I have, I can't see it being a failing power supply.

Edited by deleted (Sat 23-Feb-13 10:53:21)

Looking at that graph, and I have seen hundreds, suggests that the problem is an external noise source causing interference on the line. It could be your apartment, a neighbour or even someone down the street.

Looking closely there are five spikes occurring. The line is stable with a little fluctuation, spike, after which the noise fluctuates quite a lot, another spike, and so on ... The spikes are likely to be caused by a motor or pump starting up, or a CH ignition system and then the fluctuating noise from a motor of some sort running.

You say CH is on 24/7 - but what are the temperature settings? Is it set for 20^ofrom 04:30 to 09:00 and 16:00 to 23:00 and then just 14^o for the rest of the day?

I've just tested the phone directly into the test socket and there is definite noise.


Our thermostat is just set to keep the room at 20C, it comes on as and when it needs to. I've taken the batteries out of the thermostat and turned it off at the MCB, still noise. It's definitely nothing in our apartment causing the noise as far as I can see.

I've got 3 filters, one of them brand new fitted yesterday. I can't see 3 of them being faulty.

Is that "I have three filters and I've tried them all, one at a time" or "I have three filters plugged into various phone points" ?

Tried the test socket to eliminate internal wiring ?

Sounds like a line fault or filtering issue from the information so far.

Wouldn't a failed filter tend to show up as some sort of hiss (or other fairly steady noise) on the line, rather than snap, crackle and pop?

probably, but he's getting audible noise in response to the router coming on-line which sounds like a filtering issue or a high resistance fault acting up.

If it was a dry joint the effect can be to pick up lots of RF noise

Not sure if the original poster has tried a different router, as it may be an issue with that

I've just tested the phone directly into the test socket and there is definite noise on the line in the test socket.