I started my service with VM around October 2021. My broadband up to now has been, for the most part, flawless and remedied the main reason that I ended my contract early with Plusnet.
However, sometime in the last week or two (I cannot place an exact day or time, but around the first week of February 2022) I have been experiencing very high latency spikes at relatively short intervals. This is most noticable while in meetings at work (I work from home) when my video and audio would pause/freeze for my colleagues trying to listen to me, and then extremely noticable in my online gaming experience when the game would have extreme rubber banding or just disconnecting from a server (this was in Rocket League). It's important to point out that these are all on ethernet connections.
I have since followed VM's advice and restarted my router, removed network switches, replaced cables, and factory reset the router. Nothing has fixed the latency issues. Even testing a direct router to ethernet cable to laptop connection yields the same latency issues. Since then I have set up a BQM (see below).

Every spike you see here is my boss asking me to repeat myself for the 3rd time, or my Rocket League team getting scored on because I missed a save where the ball teleported above my car.
I will post my router status logs in a reply to this thread. I've been lurking in this forum for a couple days and know that VM will often 'oversubscribe' an area. If someone in the community can have a look at this data and let me know if this is similar to that situation I would be very thankful. The one thing that seems odd to be is that if it were an oversubscription issue then I would think this issue would have gradually gotten worse, not the sudden shift that I have experienced.
I would also appreciate if someone at VM could take a look at this issue. I have raised a formal complaint and can provide a reference number if needed. I will keep the BQM running for at least the next 30 days.