TBB and BT Wholesale both give 15 to 17 Mbps
Speedtest.net 17 Mbps ( and I know it is often a little optimistic)
Sync is 19999 and Max attainable is around 25.5 to 26 Mbps with >10 dB SNR so it should give close to 19 Mbps and I cannot see any reason why it is slow. Minimal errors occurring - if any, short leads from modem to socket, no big unexpected dips in Bits/Tone graph and other graphs look fine too. No other devices uploading ... and is much the same at all times.
Downstream is syncing at a full 80 Mbps and gives 75.5 Mbps - so no issues there. Most recent BT test gave an actual 78.63 Mbps with 77.35 Mbps Max Achievable.
Just trying to work out what I may have missed ... as everything points towards full speed being achievable.
M H C
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