Hi @javibaluja.
Welcome to the Sonos community and thanks for reaching out to us.
I agree with @melvimbe, the Dolby Atmos Audio format needs an upward-firing speaker to simulate Dolby Atmos which is present in the Sonos Arc but not in the Sonos Beam. I would like to share with you key articles about the supported and unsupported audio format to better understand what is what audio format/codec works with the Sonos system.
I hope we helped.
Please let us know if you still have further questions or concerns. We are always here to help.
Thanks,
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