Set Samsung TV Volume to Specific Value Doesn't Work

Hey guys! Newbie to Home Assistant here

I’m having a hard time having it to set my old Samsung TV( UN32F5500) volume to a specific level on my new home server. Volume Up works. Volume Down works. Mute works. And the slider does update to the right value when the volume gets changed elsewhere, but when I drag the slider, nothing happens.

This is with a Home Assistant container (lscr.io/linuxserver/homeassistant:latest) on a Debian 12 system.

Thing is: this feature works flawlessly on my Virtual Machine Home Assistant OS. It also works when I’m streaming media to the TV through DNLA. So I guess I’m missing something here.

Does anyone know what might be going on?