Broadband up and down

Hi. I'm new here and have had a quick (actually a long) read of various posts. Very interesting. But, I have a problem that my ISP says they are going to sort out.

As of last Thursday my internet access has gone from a really solid 37Mbps down to unusable at times.
The problem is not that the router disconnects (it still sits there happily thinking it's connected at 40Mbps), but that there are very large delays even when simply browsing.

The main sites I'm using for testing are www.bbc.co.uk, www.fast.com, and www.google.co.uk.
All I'm doing in the test is trying to load a page. Sometimes nothing happens and times out.
Using fast.com shows a range of values from 0 to 37Mbps. It can cycle good and bad several times an hour, or just a couple of times a day.
Re-booting, or power cycling gets it working again. But maybe that's just coincidental, as if you don't reset, it does seem to recover by itself.
Actually, disconnecting and reconnecting in the router web page also makes it pop back into life.

I've done a quick tracert on the above addresses and when it works everything is sub 10ms. When it's in a bad mood, then some hops are several seconds.

I've replaced the router (twice), the microfilter, and this issue shows up on wired and wireless devices.

The last call to my ISP said that they had identified a non-specific fault and would send someone out. Is "non-specific" just their term for "we don't know what's going on"?

So, what sort of error would cause these symptoms?

ISP is Sky.
Line attenuation down is 21.9dB, up is 0dB
Noise margin down is 3.5dB, up is 6.6dB.
These stats are pretty much typical for the years its been installed.

Thanks.

Laggy DNS. You could try & get round this issue by switching the DNS to Manual in the router with 1 of these public DNS:

Open DNS : 208.67.222.222 & 208.67.220.220
Google DNS: 8.8.8.8 & 8.8.4.4
Norton DNS: 198.153.192.40 & 198.153.194.40

ISP DNS aren't the most reliable.

Don't think Sky routers let you change DNS settings from a quick read of Google so this would need to be done for each device.

Not sure if Sky hijack the DNS ports and reroute requests regardless of DNS server requested. Maybe some others who know more about how Sky operate can comment?

Anthony

I�d be surprised if your downstream SNR has always been that low ... the changes haven�t been around that long.

Silly season question, not just decked your halls have you ?

Try switching off all the Christmas stuff, and then power cycle the router .... does that help ? Got a neighbour�s place nearby which is festooned with new lights ?

Thanks for the suggestion.
So, when my broadband goes bad, if I do a tracert of an IP address rather than a named one, should that be OK? Or is it more complicated than that?

In reply to a post by Zarjaz:

I�d be surprised if your downstream SNR has always been that low ... the changes haven�t been around that long.

Silly season question, not just decked your halls have you ?

Try switching off all the Christmas stuff, and then power cycle the router .... does that help ? Got a neighbour�s place nearby which is festooned with new lights ?

No Xmas stuff up yet, and not noticed any neighbours with the same.

In reply to a post by TheRealGrumps:

In reply to a post by Zarjaz:

I�d be surprised if your downstream SNR has always been that low ... the changes haven�t been around that long.

Silly season question, not just decked your halls have you ?

Try switching off all the Christmas stuff, and then power cycle the router .... does that help ? Got a neighbour�s place nearby which is festooned with new lights ?

No Xmas stuff up yet, and not noticed any neighbours with the same.

How would Xmas lights cause problems by the way?

Electrical equipment, can sometimes emit signals in the same frequency range as ADSL/VDSL causing a variety of problems .... this is often referred to as REIN.

Poorly produced Christmas lights have a history of causing problems. Though in your case it sounds unlikely.

Some years back my ADSL connection became very slow every year when the council turned on the ancient festive lights strung in the trees in a park very close to my home.

I have not noticed the problem since switching to FTTC on an All In One on on my previously Exchange Only line.

Often the additional bandwidth of FTTC can mask such things.... or maybe they replaced something on the lights ?