I have the 200 Mbps Virgin Media package and everything is fine - usual download speeds and uploads speed on every service except Steam. I am getting an average of about 300 KB/s on Steam when I would usually be able to get ~20 MB/s easily since Steam's download speed is uncapped. My friend who is also using Virgin Media and has the exact same package as me is not getting this issue.
Have you tried changing the download location from steam? I used to get slower speeds regularly from steam until my Danish friend suggested i swap server to Denmark. Never had an issue since.
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