Telkom cannot find an ADSL fault

So I have been having a problem for about 6 months now. My 4Mbps ADSL one day reverted to 56k dialup speeds. After alternating making calls between Telkom and ISP, Telkom checked the line and declared that the line was fine. I downgraded to 1Mbps and the line speed seemed to be better after that.<br> <br> After a while I hoped that Telkom sorted the 4Mbps issue and that I could go back once again to the faster speed. After signalling that I wanted to go back to the 4 meg line, Telkom was unable to get my line to sync higher, and that continues to this day.<br> <br> Every \struggle"with their call centre just ends in frustration"