Rebooted server, clients access outside internet slow.

Cubox

Hi,

I am running an Archlinux server, and a Mac.
I have a working openvpn setup (until now). The config is here: http://paste.placeholder.fr/show/451/
Client config here: http://paste.placeholder.fr/show/452/
My ONLY iptables entry is the forwarding entry.
Now, my problem is that since I rebooted my server, the clients can download from 10.8.0.1 (the server) at full speed, but can't download to the outside (internet) at full speed.
They are stuck at 20ko/s. And it's not the server being slow, the server download the same file at 40mo/s.
Here are some more config from the server: http://paste.placeholder.fr/show/453/

This issue happened since I rebooted, and I can't find what. If there is any help that you guys can give, I would love to get my internet back, at full speed.

Thanks!