MacBook Pro (M1) only displays 1080p 60Hz on 4K TV over HDMI

I am having issues connecting my 2020 MacBook Pro (M1) to my UHD TV via HDMI.

When connected the TV is shows the content it is supposed to show, but only in 1080p resolution at 60Hz. Going to the display settings, there is no way to change the resolution to a value above 1080p.

I am using a USB-C 8-in-1 Hub by UniAcessories (https://de.uniaccessories.com/collections/uni-usb-c-hubs-docks/products/usb-c_8in1_hub) with a rather standard HDMI cable.

I've read a lot about cable and adaptor quality issues, but this does not apply here. Using the same adaptor and cable on the same TV input with a 2018 MacBook Pro works on the 1st try. Is the M1 not capable of recognizing displays correctly or scaling the correct resolution? When connecting my M1 Macbook to my LG 27UK850 4K Desktop Screen with USB-C, it works perfectly.

Anyone up with a solution? Thanks in advance!