OneDrive is soooooooooooooooooooooo slow!

That's your opinion, but it's not just me. There are loads of other complaints online when searching for OneDrive performance issues. Microsoft Support has just told me their senior engineers haven't bothered to respond to them since they last sent them more diagnostics over 2 weeks ago.

I suspect we're being throttled by SharePoint, as I can download a 100MB file at full rate first time, second time, third time... Wait a few minutes and try the same or a different file and it'll be downloading at somewhere between 400kb/s to 800kb/s, during which time there's no excessive bandwidth usage our end, and even running a speed test shows a throughput of 100Mbit both ways, and yet after the speed test completes (which was running during the slow download from OneDrive), the OneDrive download speed does not improve.

It's not a Windows thing either. I get the same behaviour when downloading files from one of our Linux servers hosted in a London data centre... The first few downloads are downloaded at a rate of over 100mb/s, but then suddenly the next lots of downloads are downloading at the same 400kb/s to 800kb/s rate.