I have a Telkom ADSL line (with bandwidth through Telkom Intenet). I recently upgraded from 1Mbs to 4Mbs (currently the maximum for my area).
Lately if I look at my modem admin web page it shows over time (normally a matter of hours) a deterioration in the speed at which the modem is synced. If I reboot the modem it normally syncs at 4096 Kbps for the down link but after some time it gradually degrades e.g. now it shows "Line Rate - Downstream (Kbps): 1056". The uplink speed stays fairly stable but also degrades slightly e.g. from 356 Kbps to 352 Kbps.
Any ideas what the likely problem is? Could it be noise on my Telkom line? If so, what is the best way to go about fixing this?