Kdenlive - Can't select GPU playback processing

When attempting to enable GPU playback processing in Kdenlive, the checkbox is greyed out. The movit & rtaudio packages are installed. Any ideas why this might be? I’m using Endeavour / Arch with an AMD 6800 GPU; kdenlive is installed from the Arch repos.

Same issue here, curious if there’s a possible fix.
Kernel: 6.9
GPU: Iris Xe, another machine tested with AMD Vega 8 and 5700 XT also doesn’t work.
Distro: Arch