It was actually more than 76Mb/20Mb as the engineer showed me his speed tool kit plugged into master socket and can see downstream was 130Mb and upstream 45Mb. But the exchange is limit our 80/20. So, I believe the cabinet pipe feed is more than 80/20.
Did you manage to find your line stats on your BT Home Hub 5? The maximum data rate should tell you with noise margin and line attenuation for future crosstalk.
Mine is line attenuation 10.6dB noise margin 12.8dB and maximum data rate 104409
Edited by adslmax (Fri 14-Feb-14 12:59:53)