Cannot load the theme

[qub1750ul]

I've cloned the repository in the sddm's theme folder and selected it in /etc/sddm.conf
But then, when i try it with sddm-greeter --test --theme /usr/share/sddm/themes/darkness-of-arch-sddm, the default theme is loaded and this error is shown:

The current theme cannot be loaded due to the errors below, please select another theme. file:///usr/share/sddm/themes/darkness-of-arch-sddm/Main.qml:21:1: module "QtMultimedia" is not installed

I'm running Arch Linux
Linux X556UR-arch 4.12.6-1-ARCH #1 SMP PREEMPT Sat Aug 12 09:16:22 CEST 2017 x86_64 GNU/Linux

sddm 0.14.0-3