Very slow download speeds through Vortex, normal when manual

[r3xp0p]

Hi, I'm using Vortex 1.2.9 on a Windows 10 x64 system. I have 70 mods installed for Fallout 4.

 

When downloading, any mod larger than roughly 400mb crawls along, often resting at 0 b/s for long periods (and never making it above 128 kb/s!), whilst downloads for smaller files run at 1 mb/s. These same large files also download at a good speed when downloading manually. It's only when using Vortex that downloads are choked in this way. I've attached two pictures to illustrate.

 

Please help me solve this issue, or at least understand it. I'd rather download through mod manager links if possible.

 

Thanks