The Sonos Arc is not directly compatible with your Xiaomi Mi Projector 150" via HDMI if the projector does not support eARC (enhanced Audio Return Channel). Most projectors, including the Xiaomi models, only have ARC (Audio Return Channel) and no eARC function, which is required for the transmission of Dolby Atmos and other high-quality audio formats.

To use the Sonos Arc with your projector, you may need to use an eARC-enabled receiver or a special HDMI switch such as the HDFury Arcana to transmit the audio signal correctly.