Tp-Link WDR4300 V1 - issues with wan speed

Hi @Doppel-D...

I don't use SQM QOS in OpenWRT 18.06.5 and the firewall, I can disable it completely for testing ...

flow offloading software, does not exist or is not installed in my configuration ...

I was going to start testing with my old 1043ND, based on this post => Qualcomm Fast Path For LEDE, more exactly here =>
https://github.com/gwlim/Fast-Path-LEDE-OpenWRT

Thanks