Download speeds have reduced and upload speeds gone up with the latest version of yamux

[mathews-joseph]

Hi Team, first of all, thank you for the fantastic project.

I've noticed that the download speeds have gone down and the upload speeds have increased with the latest version of the yamux module (v0.1.1).
I was using an older version (commit 0bc27b27de87) of the module before upgrading to the latest version.

Please find the difference in speeds in the table below. A single stream was used to upload/download a file and the target server was based on https://pypi.org/project/uploadserver/:

Transfer Type	Commit 0bc27b2	v0.1.1
Download	308.3 MB/s	265.6 MB/s
Upload	206.8 MB/s	273.4 MB/s

Please let me know if you need any further details to investigate the change in transfer speeds.