Dell Optiplex 7080 very very slow WLAN Upload! Intel AX201!

Hello together

I have a new Dell Optiplex 7080 with the WLAN module AX201. With the Internet Speedtest I noticed that the upload speed is extremely low. Download is OK. Goes via WLAN AX, WIFI-6.

I have other computers with this Intel WLAN card, no problem there at all. Upload and download identical.

Download at Dell around 500MB, upload only 15MB!!!

I googled, checked all settings, loaded the latest drivers, actually did everything. All settings are exactly the same as the other devices. That can't be the reason. Likewise, I have not installed smartbyte and no "killer"... that I found on the net as possible trouble spots.

Thank you very much for any advice.