Hi, I have had this issue for a while now, had engineers come out a few times too to check out internet and they all say the same thing, that the power through our cables isnt strong enough so it spikes, they keep telling us this but nothing has been done about it for months and months!
It's got to the stage now where its getting beyond a joke really, something needs to be done now as when speed tests get run the download speed averages 40-50mbs download and 8-10mbs upload, but still I get these constant spikes of high ping and lag.
Sorry to hear you're getting lag spikes. I've checked your connection and can see that your upstream power levels are too high which will cause your speeds to fluctuate and the latency to become unstable. This is likely what you've been told before when you mentioned power through your cables. What needs to be done to fix this is to get a technician out to adjust this. I've just sent you a private message to arrange the best time.
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