Lowering Noise Margin

I am new to Sky and don't know how good or bad they are at responding to requests.
Basically my line is capable of a better throughput than what I now which is 15.5 meg
The router SR101with firmware 1.15i.2202.R, connected at 18695 kbps
Downstream attenuation = 13.5 dB
Downstream noise margin = 6.4 dB
Is there any way that the noise margin can be lowered by my request?
Has anyone been able to if so, how.
15.5 meg throughput is not slow but with Zen my former ISP I was getting a throughput as high as Sky connection speed and that was on a 3 dB noise margin so I know the line can do it.
I live 700 metres from the exchange and have always had a good line.
BTW I only left Zen because of finances; they have a brilliant set up which I would recommend to any one.

Edited by deleted (Fri 08-Mar-13 23:06:11)

You should be getting 22-23 Meg sync speed even now with 6 dB NM.

Your throughput is correct for your sync speed; it is the sync speed that you need upping.

I just phoned up and they removed the limit, so my downstream SNR is around 3 (ie traditionally where it should be - 6 is far too stringent)

Reason I phoned was after the initial DLM it was stuck on 9db so I was getting rubbish speeds. They removed that cap there and then and I resync'd almost straight away at the much higher speed.

If you phone and sound like you're a 'technical' user by mentioning SNR etc they ought to do it

In reply to a post by Gypsydog:

Is there any way that the noise margin can be lowered by my request?

Short answer is no.
The system Sky has to profile lines only has the option for 7/9/12/15 dB noise margins.
Only way to get it lower is have it set to 7/7 and get dlm ran on the line again,
The dlm system has more options to pick from than the gui interface.

If you line is stable dlm will drop it on to a 3dB profile.

Edited by deleted (Fri 29-Mar-13 21:17:54)