Download speed cap

As of recently, I cannot download any mod with speeds over 400kb/s. The download takes a few moments to appear in my downloads list after choosing a directory to download the file to. The first ~5 seconds of the download show climbing speeds, and then a consistent plummet down to 380-400 kb/s.

• adblocker is off
• activating a vpn produces the same 5 second climb then plummet effect mid download
• account is not premium
• not an internet download speed issue
• site cookies are cleared
• does the same on every browser tried

Sounds like a niche problem, but maybe somebody has a fix. Worth an ask. Thanks