Looks like the format being supported is based on the "System on a chip platform" they use. Sonos is NOT a chip company so the chip is being outsourced for sure. My guess is if they use a common chip, they would have access to all formats but maybe they got a dolby specific chip as well.
Qualcomm Technologies International, Ltd., a subsidiary of Qualcomm Incorporated, announced today that the MAPX audio SoC family now supports the DTS Virtual:X® post processing audio solution, which is designed to deliver immersive sound to consumerswww.qualcomm.com
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