I've not long had Virgin Media installed, around about 2 weeks. I've notice from day one that there have been a few issues with the upload. Download side of things, everything is fine.
I rarely ever get the full 35Mbps upload, it normally hovers around 28 tops, but tends to fluctuate between 15 - 28 mostly. Another issue I notice is random stalling when I request a webpage. It can last for around 20 seconds, then everything returns to normal. It's not related to specific websites, its just random.
I am using a hub 4 in modem mode with a Netgear Orbi RBR750. The device I'm testing on is hardwired into the Orbit, and has a 1 Gigabit network card.
I set up a BQM once it was installed an I've noticed that whenever I start uploading, the graph shows latency increasing, and sometimes a bit of packet loss.
So I decided to run some tests on the upload, and a continuous test of upload and download is showing that while download is perfectly fine, the upload side is losing around 1%-5% of packets sent.
Looking into the logs on the modem I'm getting a few T3 Timeouts and the modulation isn't correct on all of the channels.
Attached are some test images and stats/logs from the hub 4. Regarding how our Virgin Media is delivered, its via RFOG and I've checked all the coax from the router to the ONT is tight. The ONT plug light is always solid green so it doesn't look like its cutting out either.