Very strange spikes on BQM

Can any one offer a possible explanation for the spikes on my BQM

https://www.thinkbroadband.com/broadband/monitoring/...

They come exactly on the hour at 5 hour intervals. They have been happening for the last week or so.

ISP is VF over CityFibre which has been trouble free for the last 3 years using my own Asus router.

They are not causing me any problems that I notice, the preciseness of these spikes I find very curious.

Could be your ISP, could be your router running a task/schedule of some kind or it could be any device on your network.
It will need some trouble shooting by yourself to narrow it down.

Try disabling your WiFi just before the 5 hour interval. If it still occurs it isn't a WiFi device. If it does then it is a WiFi device causing the spike.
Try the same with the connected Ethernet devices.

If none of the above testing stops the spike then disable WiFi and disconnect the ethernet clients and see if it still happens.
That tells you it's your router or your connection.
I would probably start with this test which would immediately rule out all your connected kit.

It's probably some ISP kit somewhere in the chain running a task every 5 hours.

Edited by j0hn83 (Wed 14-Dec-22 20:42:19)

Thanks John for the suggestions, I will try them and let you know.

I use Merlin firmware on my router and coincidently recently updated to the latest firmware, I thought this was maybe the cause so reverted to the previous firmware but it was still the same.

Edited by bingobill (Wed 14-Dec-22 21:09:44)

Seems it's vodafone's problem. Can rule out Cityfibre as I have the spikes on openreach. There's an active thread on the vf forum.

Seems it was fixed overnight.

https://www.thinkbroadband.com/broadband/monitoring/...

I had this exact thing on a VF FTTC circuit, I wasn't too bothered by it though as it wasn't causing any problems. I assumed it was their router doing automatic speed tests, but it's gone away now.