Just one USB device

I received my Core Plus but i have the problem (well i think it is one) that i can not connect more than one device to the USB port.
- I tried a USB Hub with and without extra power supply
- I tried to use the Micro-B but also no function
- I tried an ethernet USB adapter to use PXE also no function
- I tried different BIOS settings but nothing seems to change anything
Am i do something completely wrong or is my device broken?
Comments
What are the multiple device you are trying to connect?
What Power supply are you using with the UP Core Plus?
We have tested few hubs and in particular this one works very well: https://www.amazon.de/-/en/Aluminium-Ethernet-Splitter-Chromebook-Ultrabooks/dp/B0792S3SMB
Used to the main USB3.0 port, you can add a USB wireless dongle for a keyboard/mouse set, a USB memory Stick and an ethernet cable at the same time and it works fine.
What are the multiple device you are trying to connect?
What Power supply are you using with the UP Core Plus?
Ok, i used this
https://www.amazon.de/-/en/Lightweight-Aluminium-MacBook-Microsoft-Surface/dp/B07FPFKL4X/ref=psdc_1626220031_t3_B00Y211AFM
https://www.amazon.de/gp/product/B01LFCS0Q2/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1
and also two different Display integrated HUBs, but i will also buy yours to try it, i thought every hub will work.
does the bootable USB with Windows 10 works on other systems?
Does the USB works if you connect it directly (just the USB with Windows)?
Then you can request an RMA for your board on the UP Shop
Thank you for your support