Sync Upload Speed

I have been syncing some of my content using plex cloud sync to amazon drive. The problem I am encountering is the upload speed seems to only be at 10Mbps. My cap is at 30Mbps. Is there any way to saturate this? Using Amazon’s desktop app I get to 30 Mbps. I did go into the network settings and changed the upload speed from 0 (which I assume is unlimited) to other settings and it didn’t seem to make a difference. Any thoughts? Thanks.