GL-AR300M16 wireguard VPN download under 1mb (but upload ok)

Hi all,
My setup involves using the GL-AR300M16 to connect to a mobile wifi hotspot (a Galaxy s24 ultra), and to my laptop using a wired connection, so that I can use the VPN client to tunnel my laptop's connection (I can't install VPN software on the laptop). I am running the latest firmware (4.3.11), and haven't made any special tweaks to settings or installed extra apps.

I am trying to use Mullvad VPN with Wireshark.

When testing from my smartphone directly, I get about 42mbps download and 52mbps upload without the vpn, and 40down/33upload with the vpn (through the wireguard app on the smartphone, with the config file I downloaded from Mullvad).
(There is a high variance of up to 10/20mbps honestly when repeating tests, but still consistently above 25)

When testing from my laptop (wired connection to the router and then the smartphone's hotspot), I get less than 1mb downlad / 25upload using the glinet VPN client. My best test using the VPN is about 7mb download, but it is really frequently under 1mb, which makes the whole setup unusable for me.
This is very disappointing.

Is there anything I can try software wise to improve the situation?
Should I just replace the router with a more powerful one? Which one would you recommend? (I would prefer something similar which can be powered over USB, even if more expensive).

I am particularly surprised by the fact that the download speed is so low while the upload one is fine, so I hope it is a software issue....

If you are using Mullvad wireguard, the speed should surely not be that low.

So seems something is wrong.
Pls test:

  1. Disable Wireguard on the router and test speed on your laptop.
  2. Check if you laptop have another layer of vpn? If yes pls disable that.
  3. Change one Wireguard server and test again.

My laptop does not have any other vpns.

I tried changing servers. I get (can only post one image):

  • Using wireguard on mullvad USA_us-nyc-wg-302
  • Using wireguard on mullvad USA_us-atl-wg-001: 1.61 down / 24.85 up / ping 171 165 289 (test with a server in Atlanta as expected)
  • No VPN: 40 down / 44 up / ping 21 263 52 (and my phone's correct data provider/location)

This is all from the laptop with a wired LAN connection to the router which is connected to my phone as hotspot. Only difference between tests is changing vpn in the glinet web interface.