should I ask to increase noise margin?

I've been having problems with dropouts. About once every 30mins to 1hr. My connection is ADSL provided by BE internet.

My router gives these stats:

ADSL Link Downstream Upstream
Connection Speed 5745 kbps 1191 kbps
Line Attenuation 48.0 db 26.9 db

These are pretty stable. Sometimes the connection speed is lower.

Most of the time I get noise margins close to:

Noise Margin 6.0 db 6.3 db

At bad times, before dropping, it can go down to:

Noise Margin 3.8 db 5.8 db

Should I ask BE internet to increase the noise margin? What should I tell them? 1db, 2db, 3db more?

For each db of extra margin, how much is speed reduced?

Thanks!

http://www.coolwebhome.co.uk/calc/index.php?param=RG...

Suggest at a 9dB target you will drop to 5177 Kbps

Done. Thanks for your help!