Own router on gigfast slow speeds

[davetron]

So I got my internet installed and decided to use my own router its a qnap qhora 301w.

I got my log in details created the vlan and it connects , done the mtu settings etc .

Now the issue im getting is i get 930 down and 930 up via the wifi but hardline connection i get 930 down and anywere between 11up or 500up and more .

I decided just to use the vodafone router for now and just use the wifi on the qnap as its wifi6 would of preferred to use the qnap fully but with unstable speeds on the hardwire .

Anyone have any ideas ?  

[Cynric]

@davetron  Simple things first, swap ethernet cables and try other LAN ports on the router.

[davetron]

First thing i tried.

new cables

switched from 10 gig port to 2.5gig ports and 1 gig ports . even direct connected to computer and bypassed any other network setup .

Its so strange , if i change ports for example i use 10 gig port i get 500 up at times , i use 1 gig port i get 11meg upload . 

vlan is set up and the other ports which are bridged all seem to be setup correct .

[Ripshod]

Have you updated the firmware on the qnap? Did you factory reset it and manual setup after? MTU 1492?