Speed well below guarantee, support is not helping
I have been with Virgin for over 3 years with their fastest home broadband package (1Gig) and was so happy with their performance that I decided to bring them to my new address after moving to a new flat.
Right after finishing my move, I had to log a complain because the internet did not come on after Virgin confirmed that the line had been activated. Virgin sent an engineer out after several unnecessary back and forths with their first line technicians. The engineer found that the previous tenants of the new property had cut the outside coaxial cable leading into the inside of the flat. He patched up the cable in a few minutes and left. This restored the internet line to the inside of the premises, but it runs nowhere near the speed it is supposed to.
With the exact same network setup as my previous address, where all multiple devices could regularly reach 900-1000 Mbps speed simultaneously, I now struggle to reach 250 Mbps, which is nearly half the minimum guarantee (565 Mbps). The average speed is closer to 180 Mbps.
I logged several complaints with Virgin and two engineers came out to replace the filter box and the router respectively which didn't have any effect on the speed, as I suspect that the coaxial cable leading into the property wasn't repaired properly and would need to be fully replaced instead.
I have run several tests using a single device wired in via Cat7 and no other devices on the network with the router on factory settings, and the max speed I can reach is around 450 Mbps outside of peak times.
I know my LAN setup is not the problem because I literally am an IT engineer with 8 years of experience and know what I am doing. Hate to repeat myelf but I literally had the exact same network setup (same cables, same devices) at my previous address and never had any issues. Virgin's help line is basically useless as the 1st line technicians clearly have no experience and keep suggesting basic troubleshooting steps like restarting the router or moving my device closer to the router to get better signal even when explicitly told that I am wired in via cable.
One of the technicians on the help line pointed me towards www.samknows.com/realspeed and used it as proof that the issue is in my LAN setup because the site showed that my router is receiving 1140 Mbps speed. This is beyond suspicious for several reasons: firstly, as an IT engineer myself, I had never even heard of this website before (fast.com, speedtest.net, and speed.cloudflare.com are more common options); secondly, a quick search shows that samknows.com is partnered with Virgin Media; lastly, I have confirmed with colleagues and friends who are not with Virgin that samknows.com does not work for them at all. The tests feel biased and rigged to show whatever speed Virgin says on the contract.
At this point I am beyond frustrated as I am paying for one of the most expensive packages and receiving less than a quarter of the speed I am supposed to. I have raised so many tickets and complaints with Virgin that my account has been soft-locked and I can no longer raise new ones. Attempts at doing so brings me to an automated self-help loop constantly asking me to factory reset my router.
The issue has been ongoing for months now and is whittling down at my patience, to the point where I am considering to cancel the contract altogether and dropping Virgin as my provider.