Slow artifact download

Hi,

I am running a team city server on dedicated Windows Server 2019 machine.  I am experiencing very slow artifact download speeds (<500KB/s) resulting in our rather large (1GB plus) artifacts taking nearly an hour to download. 

I have followed the instructions from the FAQ and ensured the connectors are properly configured to no avail.

I also have tried downloading the same artifacts locally from a browser running on the server and the same artifact downloads in <10s, which obviously points to an external network bandwidth issue.  I have however tried multiple other methods of serving the same artifact (IIS, SFTP and Jenkins) and the external download speed is at my local connection bandwidth limit (7-8 MB/s over a 75Mb/s connection), the download completes in around 2 minutes.  I have tried using the same external port with other servers to rule out any firewall issues, there is no additional antivirus beyond that of Windows defender.  I am at a loss to explain this.

Can anyone help me?

Thanks in advance,

Alex