I've been having this problem for around 8 years now, and have posted relentlessly about it over the years. We've had engineers out, new hubs, and nothing has fixed it. We are on BT Fibre but being in the countryside we get around 15 Mb/s (which I'm happy with, when it works).
The problem: Every day, at random points, the latency will spike from around 20-30ms to an unusable 1000-3000ms. It happens at seemingly random points, and affects every device on the network. Not only does it become extremely laggy, there is upwards of 75% packet loss. Obviously this is frustrating and the "lag" usually lasts between 30mins - 2 hours before dropping (only for it to happen again later).
Things it's not caused by: Another device using bandwidth, I have made sure to test this and even then another device downloading would not raise the latency by this amount. It's not a hub issue as we've been through multiple routers, currently using a BT Home Hub. It's not bandwidth hogging from neighbors as again, this wouldn't result in such high latency.
Things I think it's caused by: Maybe a hardware issue on BT's end, although our exchange was recently upgraded to 21CN so it can't be exchange congestion. A wiring issue in our house maybe? Although this wouldn't explain why it only happens sometimes, at random points. Throttling? Again, I doubt it'd cause this much of a degradation in performance.
I've tried to run the BT wholesale test during one of these lag spikes, but it failed to load (it got as far as the latency test). Below I've attached Pingplotter results (which oddly enough under-exaggerates just how bad it is) a Discord (VOIP software) latency measure showing the true latency, and the BT Test that registered the latency then failed.
I know packet loss should show up on the last hop if it's affecting it, but the odd thing is that when the internet is working ok, hops 4/5 only show minimal PL, whereas here its upwards of 50%.
Anyone got any ideas? It's got to be something physically related to the network infrastructure we're on.
You have to get your head around the fact if the destination shows 0 packet loss then you have none it matters not what intermediate servers return.
been having similar problems, had multiple engineers out but no fix and one has stated that latency is not one of their problems they particularly care about. the problem for myself has been since April of this year and i honestly cant imagine it lasting 8 years. i have spent countless hours trying to fix this for myself but no luck, got to a point where i think of just changing provider to see if that changes anything as it basically just makes the internet useless. even the hotspot on my phone is more stable.
We have also been having this issue. April this year we upgraded to the SmartHub2 and had constant issues with latency ever since <400ms Ping.
Unfortunately I am not the account holder, my in-laws are, so I don't have the account details to contact to get it resolved. They are reluctant to call as they are always on the phone for 3 hours with no resolution so I resort to looking on the forums for a resolution but all of the topics relating to ping and latency all lead to one outcome.... Change ISP.
Until we move out I have opened up a contract with Vodafone for a mobile 4g router that I use on a permanent basis. I can play games again which is nice, but it can be a little unstable due to it being 4g. But WAYYY more stable that the service we current receive from BT.
Our house sale completes soon and we will definitely not be going with BT. I think Virgin Media is the way forward as I've never had any issues with them.