Sync speed drop after FritzBox replaced Zyxel

Hi all. I recently took up Zen's offer of rental reductions as part of the now-expired Big Deal, err, deal. They kindly sent me a new Fritx box router to replace the Zyxel VMG810 I had before. At the same time, I converted from Fibre 2 to Fibre 1 because I was getting sync around 38Mb/s from my line, so it wasn't really worth the extra cost for Fibre 2.

On installing the router, it wouldn't settle - was getting continuous DSL drops for about 3hrs. Putting the Zyxel back immediately stabilised the line. After a day or so, I put the Fritz back in and it dropped a couple of times, then stabilised. However, it was synching at about 35Mb/s. Since then, about 12 days ago, the DSL line has dropped once or twice each day, each time re-synching at a slightly lower speed. It's now settled at 32.4Mb/s, quite a bit down on what's been achievable prior, acknowledging the change to Fibre 1.

At the same time, the downstream SNR has increased from about 7/8dB to 11/12dB. I'm seeing occasional periods where a number of unrecoverable errors are detected on the line - not large numbers, the maximum was about 200 in an hour. Mostly, it's zero.

I've tried changing the line settings on the Fritzbox to favour stability, but that had little apparent effect so all of them are set to favour performance. Line stats, below:

Receive Send
Max. DSLAM throughput kbit/s 32400 10000
Min. DSLAM throughput kbit/s 128 128
Attainable throughput kbit/s 42259 9378
Current throughput kbit/s 32398 9378
Seamless rate adaptation off off

Latency fast fast
Impulse Noise Protection (INP) 43 0
G.INP on off

Signal-to-noise ratio dB 11 5
Bitswap on on
Line attenuation dB 23 37

Profile 17a
G.Vector off off

Carrier record A43 A43


Seconds With Not Remediable Errors (CRC)
Errors (ES) Many
Errors (SES) per
Minute Last
15 Minutes
FRITZ!Box 41 13 0.13 7
Central exchange 487 2 0.76 21

Before I awitch back to Zyxel, possbly resetting something, is there anything else I should try to speed things up? Would Zen be able to do anything to restore the lost capacity?

TIA,
PP

Edited by Pablo_Pablovski (Thu 14-Sep-17 19:31:36)

More stats stuff.

Online Time Data Volume (MB) Connections
(hh:mm) Total Sent Received
Today 19:32 1817 119 1699 1
Yesterday 24:00 870 78 792 1
Current week 91:29 7011 538 6472 4
Current month 276:15 25773 1483 24290 98
Previous month 0:00 0 0 0 0

I have used Fritz!boxes (7390/7490) on my Zen FTTC line for over 5 years without any major issues. Indeed, my stats show a constant 74.7/20 connection since mid July with a very low error rate. My downstream SNR is 5 on an ECI cabinet. I do set up my Fritz.boxes manually using the advanced settings menu.

AVM Berlin are extremely good are analysing the inbuilt diagnostics and the boxes do come with a 5 year warranty.

Somewhere in the settings on mine is a "slider" between speed and stability. Make sure it's set all the way to "speed" (or similar).

I got the 'free' Fritzbox with my upgrade to Fibre 1.

I eventually gave up with it and bought myself another DrayTek (my old Draytek 2600 was too old for fibre)

Edited by Sandgrounder (Sun 17-Sep-17 21:55:44)

Thanks, I'd done that after lowering the settings toward "stability'. Didn't make any difference as far as I could tell.

The sync speed has continued to drop, it got to 27Mb/s after the line re-sync'd today. I phoned Zen support who were very helpful though the issue persists. I swapped the Zyxel back in and it snyc'd at the same speed as the fritz so it look like the BT line management is keeping speeds lower than optimum. I'm told not much can be done since the speed is within the estimated range available. The fritz box is back in and I've to call again on Friday to see how it's been. If problems persist, Zen send out a replacement router. Bit of a faff, and disappointing because the router reports a max attainable speed of 43mb/s,so it should be able to support akt more than 27mb/s.

Thanks, I have the Zyxel that was very stable at 38mb/s since I upgraded to fibre in Feb. Sadly it's now synching at the same reduced speed that the fritz box has reduced the line to so I'll defer any purchases until I know the BT line management tool is allowing the line to synch at the highest rate possible. Appreciate the recommendation though, I'll look into Draytek.

During the call to Zen today, we reset the settings to default on the fritz.box, plus I'm now connected to the test socket. No improvement so far, but I'll give it a few days before calling back.

Well I have a FRITZ!Box 3390 (Modem / Router) and a FRITZ!Box 4040 (Router) and my brother also has a FRITZ!Box 3390 which he is still currently using on his Zen Unlimited Fibre 2 package and he hasn't had any issues at all.

My 3390 went faulty not long after I got it, couldn't be bothered to send it back so I repaired it myself, turned out there was a broken track under the isolation transformer for the DSL connection, this then went on to work great while on ADSL2+.

Upgraded to FTTP late last year, so I brought the 4040 which worked great for about 10 days where it then started to get huge packet loss every 6 hours, wasn't too sure if it was the 4040 or my line, so I brought a Linksys WRT 3200 ACM which has the odd issue with IPv6 which you have to faff about with to get working, but the line is great going by my BQM in my sig.

Not too sure on what Fritz Model you are using, I assume its the 3490, not used that model myself, but it looks exactly like the 3390 but with USB 3.0/2.0 ports.

I say give the Fritz a go, you have a free Static IP, so I would setup a BQM if you haven't already and let that run and just compare them when you get issues, that's what I have been doing and mines been clean and flat.

Paul

These are my stats with a stable connection 74.7/20 from the 27th July. Downstream SNR 5. All performance sliders to the right.



FRITZ!Box 4084 0 0.05 1
Central exchange 632 102 0 0

I am using a 7490. The 3490 is effectively the 7490 without the PABX functions. My connection is rock solid on Zen GEA backhaul.