Several years ago, I read on the forum that if you started streaming Deezer using a voice command from an Alexa device (button), the Deezer stream would not be FLAC.  I paste the response from that thread below:

“Alexa will play Deezer in 320 kbps AAC/MP3 formats, not FLAC. This doesn't change based on account type. A stream started using the Sonos app will be at the higher quality formats which you can then change to the next queued track, or skip songs using Alexa. Along with the other Alexa standard controls.”

However, someone from SONOS customer support most recently told me in phone call that this was not true.

I am unsure who to believe.  Can anyone clarify?

Thanks.