Well Xmas eve came and lo the Magi did it - the new port seems to solved the problem - alleluia thricely.

Just for your convenience, these are my new stats, beginning with noise margin
Router Statistics

System Up Time: 205:13:19
Port Status TxPkts RxPkts Collisions Tx B/s Rx B/s Up Time
WAN PPPoA 62244 94147 0 75 730 42:42:05
LAN 100M/Full 759939 526998 0 1126 121 205:13:15
WLAN 11M/54M 36002 0 0 7 0 205:13:02
ADSL Link Downstream Upstream
Connection Speed 8160 kbps 384 kbps
Line Attenuation 21 db 5.5 db
Noise Margin 10 db 13 db

and then the whole of the rest
Router Status
Firmware Version V2.02.34
MAC Address 00:1b:2f:a1:38:5f
IP Address
Network Type PPPoA
IP Subnet Mask
Gateway IP Address
Domain Name Server
LAN Port
MAC Address 00:1b:2f:a1:38:5e
IP Address
IP Subnet Mask
ADSL Firmware Version
Modem Status Connected
DownStream Connection Speed 8160 kbps
UpStream Connection Speed 384 kbps
VCI 38
Wireless Port
Name (SSID) SKY27037
Region Europe
Channel 1
Wireless AP enable
Broadcast Name enable

and speed tests are averaging 6 to 6.5 on the richter scale.

Any comments on the stats welcome of course.

So, problem solved. But I have to say this has taken 6 weeks so to do, and god knows how many buck passing Tier 3's to get it to this point. I note that no one from Tier 3 has called me to ask if the work had solved the problem, and I doubt anyone will. Poor, abysmally poor, customer service. Someone needs to grab Sky Broadband customer services by the neck and throttle it. There is a clear assumption that customers are stupid - thus the nonsense of a Tier 1 - Virgin do not have that crap, you are immediately thru to a person who is technically sussed and willing to help. Even the last person I spoke to began by saying the fault was on my side -wrong drivers, TCP settings - only after harranging him that this was not good enough did he come up with the idea of changing the port at the exchange. Prayers that nothing else goes wrong - I doubt I will be renewing Sky after a year.

Thanx, however for all your kind attention and hands up to the man who spotted the last resort!