I go back to my original gripe, I think my line is so poor that I will never get a good service until BT openreach do something about it, either repair it ( I'm more likely to be hit by meteorite than getting it repaired) or giving me another d-side pair( again trying to get that will be near impossible)
If the engineer saw 40Mb at the socket & re-checked it before leaving
AND your IP Profile is still 38717 k, then unless your IP Profile is stuck, it does appear that you have the full 40Mb Sync speed.
If your line was too poor, you simply couldn't sync at 40Mb (e.g. my poor connection).
The BT speed test supposedly bypasses "normal" internet traffic routes, which could explain your higher speed test results from the BT speed checker.
One last thing, I can't find out how to check if the hubs settings are PPPoE or PPPoA. It's a Home Hub 3
I'm not convinced this is a router problem, it was just a thought regarding solving things via a process of elimination.
I'm not familiar with any of the home hubs at all, but from another forum:-
You can actually get online using no router too, just the Openreach modem connected directly into a computer via ethernet or into a network switch.
This has been incredibly handy for me as my Home Hub 3 has just competely died.
In Windows, go to Network & Sharing Centre, click set up a new connection or network. Then select 'connect to the internet'. Set up a connection as PPoE using bthomehub@btbroadband.com as the username (no password). That's it!Trying that
MIGHT just help to eliminate a home hub problem
Without access to an unlocked HG612, or an alternative (really expensive) modem, there is no way you can check your own Sync speed, attenuation levels, Interleaving depth, error counts, SNRM etc.
Until you have absolute confirmation from your ISP that you are actually syncing at 40Mb, all the rest is pure guesswork.
The only other thoughts I have at this stage are:-
Possibly your MTU / rwin settings may need some adjustment to match the home hub's settings, but again, that wouldn't really explain the differences in speed tests you have experienced.
I don't know how to change those settings as I have never needed to.
Final thought is contention.
It could be that a person or persons nearby are 24/7 really heavy downloaders, using massive amounts of bandwidth that affects your throughput, but not your sync speed.
Have you reported this to your ISP's customer support lines?
If so, have they suggested anything?
If not, I would suggest you either make the call or use any of your ISP's online support tools to report it.
Paul.
EDIT:
FYI, This is the sort of detail that my ISP (Plusnet) provides:-
GEA:
Test Outcome: Fail
Test Outcome Code: GTC_FTTC_SERVICE_1603
Description: Daily downstream line rate less than fault threshold rate. Continue submitting trouble report
Main Fault Location: DT
Sync Status: In Sync
Downstream Speed: 27.9 Mbps
Upstream Speed: 6.0 Mbps
Appointment Required: N
Fault Report Advised: Y
Profile Name: 16.2M-32.4M Downstream, Interleaving Low - 3.6M-7.2M Upstream, Interleaving Off
Time Stamp: NA
RADIUS: One Day, 20:13:46 (on going)
Summary: All within limits.