Groundhog day on my telephone line

[#1]

Last September I raised question  22968309 re poor sync speed appalling download speed alongside noise on the voice signal etc etc etc. which got fixed eventually
Well it has started again, sync speed has dropped, noisy phone line, Talktalk do a line test (as they did last time and say there is no problem (as did PlusNet ) 
Is there any way we can get Openreach out to check the line again - last time it was a faulty connection at the top of the local telegraph pole.
The thought of going thru the ping pong of repeated questions about interleaving etc  and taking several weeks to getting it resolved is causing me to go into a steep decline -
PLease

[#2]

Hi drw.
Sorry to hear that your having problems.
We'll need to get the noisey line sorted before we can resolve the adsl issue.
Couple of questions. Is the noise evident when your modem / router is disconnected from the phone line?
Have you checked / replaced any filters you may have.
Do you experience noise at the master socket with all other telephony / internet devices disconnected?
Is your  phone service provided by Talk Talk? I am assuming so based on your post.
Do you have a spare telephone handset to test with perchance?
We need to get the phone line sorted first as we cannot progress the adsl fault while that is still apparent.
Post back if we can do anything further.

[#3]

Hi Mark
Talktalk are "providing " the line and service for voice.
I have tried talking to them on two occasions and because their line test shows no fault (as it did last September) they are reluctant to take action.
So the noise exists - like it did last year.
The continuous hissing noise stops when the router is switched off - however the  crackles continue.  (same symptom last September)
I have swapped between three sets of filters, isolated the internal phone extensions away from the router and main handset, tested with a different handset.
I have swapped routers and still get the noise when a router is running. All the same symptoms as before (I took the same actions last year)
The sync speed is now down to 2048000 and the  speed you are reporting is 1500Kbps on the Connection Setting screen, normally it can go over 6000 
I am now going to raise a ticket with you. Repeating all this information - I hope that the question can be escalated to BT so that they can do a physical line check and resolution.

[#4]

I cannot say with any certainty what TalkTalks policy is when it comes to issues on the line when lines tests show no problem.
For the record, almost all tests performed were noise is apparent come out with a no fault found in the result.
As per your latest description, there is a crackle on the line when the router is unplugged. This itself prevents us from progressing the matter as a Broadband provider.
From a Broadband faults perspective, the service is operational. Whilst we can see the speed has dropped, the key note is that it is operational.
You do have a case to progress it further with Openreach though, as taking your service down to the bare bones with no internet, produces the crackle.
When we get a NFF (No Fault Found) result from eCo Repair (the tool used for line tests and fault tracking), we inform the customer of this. We do so, as to progress the fault can result in TRCs (Time Related Charges).
These are not cheap. There is a base fee around £80, then per hour charges with a minimum of 1 hour.
These do only get applied though were the customers equipment is the source, or they are in some way to blame for the fault (take Xmas 2006. customer got a hadge strimmer for xmas, and promptly decided to make good use of it, going through his phone line).
After informing the customer of the facts from the test results and what can happen, we ensure that customer testing has been done to the bare minimum as follows.
1: Take a single corded handset, preferably a new item or one known not to show the same symptoms on another line.
2: Unscrew the master sockets front face and carefully pull forward.
3: Plug the phone into the provided test socket without a broadband filter, or dialer box (used to obtain reduced cost calls) and try a quiet test.
A quiet test consists of dialing a single digit on your handset (eg 1), and listen to the line for the symptoms.
If you do not have a standard type master socket, but the line Line 1/2 boxes, you should replace step two with the following.
2a: Unplug every device from your line including your broadband modem, standard modems, faxes, phones, ringers, dialer boxes and importantly, sky boxes.
2b: The Line 1/2 box is your master socket, and although you cannot remove the front face, you should conclude step three from this box.
Provided the customer is aware of all this, has performed the above, we will proceed on the basis that charges would be passed on.
TalkTalk can do the very same and you can instruct them of that.
They may be reluctant, but that should not be used as a barrier.