BT HomeHub Stats

Tricky · 24-02-2011, 12:19

Firstly my broadband speed dropped by 33% at the weekend (down from 3mb to 2mb and now at 1.7mb)

I've not changed any internal wiring (I had moved it all to CAT5 between sockets before xmas)

I've tested all the places I can including the Test Socket and the speed remains the same low 1.7mb - In total I have 5 areas I can plug into (Test Socket, Master Socket, 2 in the hallway and 1 upstairs where HomeHub2 is normally installed).

Attenuation is 42.7 to 44.3 down and 25.8 or 25.9 up - So I don't think issue is that

Noise Margin is:
13.6 Up and 5.9 down in Test Socket
15.2 Up and 5.9 down in Master
15.2 Up and 6.1 down in Hallway
16.1 Up and 6.3 down in Hallway Cupboard!
and
15.3 Up and 5.9 down in Study Socket (Furthest Away and worst cable due to accessibility!)

I have 1 other device installed on the sockets (with a filter)

I have found many sites saying low SNR is good and many others saying that higher SNR is good. Cannot seem to find anything that helps me translate my stats above - Help!?

I also have a BT Engineer due to visit tomorrow morning...

MadGamer · 24-02-2011, 13:19

I have seen various posts on the BT Community forums saying that the noise margin should be around 6dB. i would plug into the test socket and leave for 3/5 days to see if things improve. If after 5 days there is no change send an email to them asking to look into the issue

qasdfdsaq · 24-02-2011, 15:53

Noise margin is configurable. SNR is not. High SNR is good, low SNR margin is good (for speed).

Tricky · 24-02-2011, 23:08

Configurable how?
Assume then that my SNR Margin Noise margin (Down/Up) 12.1 dB / 5.6 dB
Dropped since I've been out this evening is poor then?

What should it be?

qasdfdsaq · 25-02-2011, 01:53

Normally the target SNR is 6dB. Higher levels are set for stability, lower for speed.

It's configurable either by setting it on your modem or having your ISP set it for you - both of these depend on your ISP actually allowing it.

What you should really be looking at to diagnose reduction in speed or instability is noise, i.e. transmit power minus attenuation minus noise margin.

Paul · 25-02-2011, 07:15

Looks like you may be capped, a call to tech support is most likely needed, as above your target SNR is 6db so to be at 12 means you are nowhere near to your correct speed. Unless the system is seeing errors on your line you should be getting a lot more speed.
Have you rebooted the router lately?

Tricky · 25-02-2011, 09:18

I believe I am Capped too possibly due to instability? Engineer still expected before 1pm today. Router has had a few reboots trying to resolve the issues. Guessing configuration option is a no no as ISP is BT :-(

Marcus125 · 25-02-2011, 13:00

When I was with TALKTALK you could go on the member forums and ask for you line DB profile to be changed.

For me a 12db line would give my around 8 meg and be super stable. A 6db fastpath would give me around 12 meg and a very low ping but was not quite as stable as the 12db.

Sometimes the automatic line managment will change your line profile if it thinks your line is unstable. Unfortunately I believe turning your modem/router off every night can make the system think your line is dropping connection so change your profile to a slower but more stable one.

So always leave your modem/router connected and switched on.

Tricky · 25-02-2011, 13:19

BT Community Forums offer the same albeit looks to take a bit of asking convincing!

I've had my BT OpenReach engineer out who is going to try move me between two cabinets via some interconnect as the other cab is showing less loss on the line, he has also done something in the exchange called me and my new levels are:
Noise margin (Down/Up) 6.3 dB / 5.8 dB

Connection downstream is 4,331 kbps so awaiting the cap to disappear to see if this has worked.

Back at 3.3mb - Top work mr. engineer

MadGamer · 25-02-2011, 15:01

Leave the hub powered on and connected to the socket for 3/5 days and the line profile should rise

Tricky · 25-02-2011, 16:48

Quote:

Originally Posted by MadGamer

Leave the hub powered on and connected to the socket for 3/5 days and the line profile should rise

What I am hoping albeit it is plugged in where I don't want it but it is not moving for at least two weeks!

dragon · 28-02-2011, 21:05

Quote:

Originally Posted by Marcus125

When I was with TALKTALK you could go on the member forums and ask for you line DB profile to be changed.

For me a 12db line would give my around 8 meg and be super stable. A 6db fastpath would give me around 12 meg and a very low ping but was not quite as stable as the 12db.

Sometimes the automatic line managment will change your line profile if it thinks your line is unstable. Unfortunately I believe turning your modem/router off every night can make the system think your line is dropping connection so change your profile to a slower but more stable one.

So always leave your modem/router connected and switched on.

BE let me change the snr margin via their website or by asking any of their tech support team