Slow download speed with Archer C7V4

Installing and Using OpenWrt
1

Hi guys.

I've been using OpenWrt on my Archer C7 for the last 3 monts and I'm very happy with it.
Never had a problem, but last week my ISP upgraded my speed, so I went from 300Mbps to 600Mbps (Download).
The speed is still the same, still 300Mbps (Only download, upload also was upgraded from 50Mbps to 100Mbps and that is working fine) wired and wireless.
If I plug my ISP router directly to my pc it works, speedtest is 600Mbps, but as soon as I change that to switch and plug Archer C7, I'm always getting 300Mbps.

This is my /etc/config/network file:

config interface 'loopback'
        option ifname 'lo'
        option proto 'static'
        option ipaddr '127.0.0.1'
        option netmask '255.0.0.0'

config globals 'globals'
        option ula_prefix 'fdee:b4e2:a520::/48'

config interface 'lan'
        option type 'bridge'
        option ifname 'eth0.1'
        option proto 'static'
        option netmask '255.255.255.0'
        option ip6assign '60'
        option ipaddr '192.168.0.1'
        option dns '192.168.0.131'

config interface 'wan'
        option ifname 'eth0.2'
        option proto 'dhcp'

config interface 'wan6'
        option ifname 'eth0.2'
        option proto 'dhcpv6'

config switch
        option name 'switch0'
        option reset '1'
        option enable_vlan '1'

config switch_vlan
        option device 'switch0'
        option vlan '1'
        option ports '2 3 4 5 0t'

config switch_vlan
        option device 'switch0'
        option vlan '2'
        option ports '1 0t'

config interface 'vpnserver'
        option proto 'none'
        option ifname 'tun0'

And I don't use sqm.

What could be the problem here??

Thank you very much guys.

2

If you use flow offloading you might be able to get away using the C7 otherwise the simple (and only) answer is to upgrade to beefier hardware (only available on master (snapshots) to my knowledege).