Same issue as below, still reproducible 
Please check this topic
What's laughable is that a 1000€ soundbar isn't capable of decoding a mono signal, and what's even more laughable is that 2 years after the problem was reported, it still hasn't been fixed.
Sonos also does not do DD 1.0 signals. Do they promise to? In Supported home theater audio formats | Sonos no exceptions are made between mono and multi cahannel set formats…..
What's laughable is that a 1000€ soundbar isn't capable of decoding a mono signal, and what's even more laughable is that 2 years after the problem was reported, it still hasn't been fixed.
I don’t hear you laughing 
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