Help! my speeds have gone seriously rubbish

Last month when i first signed up to sky max i was getting download speeds of 2.4meg to 4.1meg (I knew i'd never be albe to get any where near 16meg anyway *sighs*) and now i'm getting download speeds of 170kb/s - 182kb/s?
I have even tried the TCPOptimizer that was recommeded and nothing has changed?
ADSL Link Downstream Upstream
Connection Speed 205 kbps 483 kbps
Line Attenuation 63.5 db 42.1 db
Noise Margin 12.1 db 7.5 db