Fluctuating attenuation?

On a WBC exchange through A&A I can switch between ADSL1 and 2/2+, and I always understood that attenuation was likely to rise when using 2(+).

However, I'm seeing the opposite, with attenuation always showing as 51 on ADSL2 by my zyxel 660HW-T1, but fluctuating anywhere between 52 and 56 on ADSL1.

And it can also vary + or - during a session - e.g. it'll show as anywhere between 54, 55 and/or 56 over a period of a few minutes without resyncing.

Curiously, I've also noticed upstream SNR is invariably lower (11db-ish) during daylight hours than at night (rises to around 17-18), and I always thought SNR would drop after dark.

Anyone know if this is this more likely to be a flaky router or something strange about the line since the move to WBC?

Stats were always relatively consistent before the shift, but I switched router from a broadcom based Belkin to the Zyxel around the same time, so I'm not sure which is to blame.

Not one of the most techy posters here but I am also with A&A, the differing attenuation that you notice on the Zyxel was something I thought most odd,

I am ADSL Max and it varied in session without resynching just as you report between 53 and 51. plus it seemed to drop synch overnight. A&A updated the firmware remotely but that made no difference

I had used Netgear 834n previously and that had always remained static re attenuation and hung onto synch to the bitter end. in trail and error mode yesterday morning I switched back to my trusty Netgear and hey presto, attenuation has been consistent at 49db for 36 hours plus it hasn't lost synch overnight !!

I shall put the Zyxel back in its packaging....

Yeah - I've been finding performance, stability and resilience all seem to be poorer with the Zyxel than with my previous Belkin, but unfortunately my son's nabbed that for his house and won't give it back because it performs so well for him too.

I wasn't sure if these problems were actually related to the exchange upgrade to WBC though, but if you've been finding similar issues with your Zyxel too, then I may just bite the bullet and pick up a different router to see if that sorts things out.

Thanks for the info.

Have you checked for firmware updates as these can make a big difference sometimes to modems

Thanks MrS... There is a newer firmware than the A&A recommended one I'm running, but a little hunting around suggests that some other people have found that to be worse in some areas.

I've also found suggestions that the chipset in the Zyxel doesn't get on well with some Infineon chipsets used in Huawei MSANs - which is what I appear to be connected to in my exchange.

All in all, it perhaps makes sense for me to pick up another router to see if that changes things.

Anyone know of particular routers which DO work well with Huawei MSANs?

In reply to a post by mistynow:

... I had used Netgear 834n previously and that had always remained static re attenuation and hung onto synch to the bitter end. in trail and error mode yesterday morning I switched back to my trusty Netgear and hey presto, attenuation has been consistent at 49db for 36 hours plus it hasn't lost synch overnight !!
I shall put the Zyxel back in its packaging....

Since you were experiencing the same, I picked up a cheap DG834Gv3 from fleabay for < £10, then configured and installed that tonight... Like yours, attenuation is now reported stable (at 52db), synch is marginally higher, and it's hung on tenaciously so far, even with SNR varying from 1-7db.

Strange that should be the case since the DG834V3 is the same chipset as the Zyxel I believe, but it's better all the same.

Looks like another Zyxel going back into the box.

the chipset ADSL firmware / microcode may be more up to date on the netgear, some Zyxels have ancient firmware on board and in general seem less likely to have been updated by the user.

i am so pleased that the Netgear may have solved your problem as well on AAISP,

Mine is showing an uptime of 145:57:05 synch 5842 with an attenuation of 49db, in therory the SNR is 6db but what the heck if it drops to 3 or so overnight it holds synch !!!

Zyxel and routerstats lite didn't like each other either but when i did manage to check Zyxel lost synch at 4db, not much use on my line.

In reply to a post by yarwell:

the chipset ADSL firmware / microcode may be more up to date on the netgear, some Zyxels have ancient firmware on board and in general seem less likely to have been updated by the user.

New firmware has been released recently and AAISP updated my router remotely in the hope it would fix the problem...it didn't