Klunk:
It probably follows that you may have an
increase in bit rate, but surely the error rate will increase in
proportion making any actual increase in speed less than it may first
appear?

But the problem is the noise on the line has random spikes, which cut off
the synch regardless of the speed !

My line used to be 2.8Mb/s and 6dB SNR for weeks on end, but sometimes cut
of every couple of days, sometimes just hours. It usually took couple of
reboots to get back to 6dB and max speed.

Now BT / DSLAM / BRAS has PERMANENTLY pegged my SNR at min 12dB and thus
throttled my speed to 1.5Mb/s, but actual download speed is just 800kb/s.

Its like this:
"BT sells you a car that will do 'up to' 80 mph.
In reality it will at best reach 28 mph, and the engine cuts out every few
days, if not hours, because the wiring is c**p.
Instead of fixing the problem, BT reduces the speed to 15 mph,
but of course it still cuts out just the same !

In real life one could get a new car or the money back,
but BT is still a monopoly and law to itself !

BT are UNNECESSARILY reducing the usability of our connection.

We now have mobile broadband, as yet it's not much better, but is meant to
improve soon. We may be giving up broadband and the BT line.....
Regards,
Martin