Synch speed down to 1000 Kbps why?

[#1]

And as predicted, PN's record of my profile has dropped to a whopping 750 Kbps.
Edit to add detail about noise margin
Just looked at my router stats and noise margin is jumping between 6.1 and 6.7 so on the basis of what has been said previously and what I've read its no wonder I cant get a decent speed.
Anything I can do further to get this to stabilise?

[#2]

Mitch,
Your service is working to design.
As per link:speed if your sync speed drops, your IP Profile will.
We cannot raise a fault based on your IP Profile dropping because of an increase level on noise being present on your line, causing your sync and IP Profile to drop.  It is how IPStream Max is designed to work.
Please read the article I've posted above.

[#3]

Ok James think we both hit post at the same time.

[#4]

The important thing now is to leave everything alone - frequent disconnects/reconnects could be interpreted as line instability by BT and prevent your IP Profile rising.
There is always a variation: yesterday I saw it as low as 7db and as high as 12db

[#5]

fair enough then if its not uncommon to see wild fluctuations in the figure.
Thanks for the replies all and my frustration is most definitely not directed at PN as you all have been really helpful

[#6]

The time to start worrying is when it drops below 5 or 6 as this could result in resyncing at a lower speed.

[#7]

Oh I thought the lower the better but from reading James' blog about speed faults, 6 is the target figure I gather.
It has def dropped since I got a router supporting DMT as per the advice given.

[#8]

@techguy
The figure is the Signal to Noise Ratio Margin - as Jelv has pointed out it will vary throughout the day.  
It will generally be at its lowest in the evening peak when people are at home with TVs and other electrical appliances running and street lights are on etc. In other words, there's more electrical noise around in the evening that will be picked up by your phone line hence lowering the Signal to Noise Ratio.  (That's the reason disconnecting the ring wire helps - it stops it acting as an aerial picking up electrical noise on your line thus giving you a higher SNR margin.)
Have a look at this post and the one immediately following by Barry Zubel.  They may help explain things.
Edit: 

Quote

I thought the lower the better

Sort of!!
If you're line as a high SNR margin there's more room for the equipment to play with before the floor of 6dB is reached. This post may help explain!
Edit: typos

[#9]

Just a thought, would switching interleaving off help at all?

[#10]

Not really at the speeds your talking about. The only speed that you'll see a difference in is at the top end (max sync with interleaving on is 7616 - it's 8128 with it off - see here for an explanation).
In fact, with your line, turning it off may make matters worse!
Edit: typos

[#11]

Thanks Paul
My knowledge of ADSL is appaling

[#12]

You're speling isnt grate eyetheur.

[#13]

Very funny, what happens when you try and multi-task
Should be appalling.
My brain often works quicker than I can type.

[#14]

To bring back on topic.
Just checked with the BT tester and my profile has raised back to 1500 Kbps and I get throughput of 1397 Kbps

[#15]

Not used my connection this morning but checked into member centre and am disappointed to find my sync has dropped to 750 again. 
Any further suggestions?
Here is my wiring config at present (BT wall socket > lead to surge protector > Microfilter plugged into surge > router fixed to DMT and with MTU of 1458 > ehternet to PC)
Should I change this config?