Upload Speed by syncing with seafile clients

Hi, I run Seafile Community Edition on my ded server. Usually, when I’m using the web end or the upload files function in the client I always have the highest upload speed as possible. But when I’m syncing, I have a speed up to 1.3 mbit/s, on Windows and Linux (Gentoo and Debian) the same. The Camera Upload on the Phone is much faster. Any ideas to help?

Thanks, Oskar