Slow download large file

[TheSonic03]

When I download large attachments of a post, like as file mp4 or psd, at the begin the download speed is equal to my actual max internet speed, after that starts slowing down very quikly to less than 1MB/s.

Seems isn't releted to a specific service.

Try to download this: https://kemono.su/fanbox/user/3316400/post/7897623 or https://kemono.su/gumroad/user/3267960360326.