I've logged a call with telkom with the same issue. The line is connecting fine to the exchange but get like 80% packet loss.
Telkom was @ my house to check the line, but they are just not bright enough to fix it. They blamed the 3month free 1MB clients and told me that these clients will get priority and there's nothing wrong with my line.
Still waiting for them to sort it out.
I've upgraded my line now from 384 to 1024, I hope this will sort out the issue.