Sonos is lossless too
"DTS also says the signal going to the speakers is lossless – again, unlike Sonos "
Sonos is also lossless (provided the source is lossless of course, such as FLAC). You can actually play a DTS encoded CD (remember those?) over Sonos and via its digital out decode it without errors in your surround sound processor/receiver. You just get digital noise if it was lossy.