This isnt correct. Airplay 2 has two streaming modes. Realtime which is full uncompressed 44.1/16 or low latency mode which is AAC. The latter is intended for multiroom when using your Phone as the source as WiFi on phones isn’t that great. What version of streaming is used depends on the apps implementation. Both can handle mulitroom but as the uncompressed one uses so much more bandwidth it’s likely to suffer dropouts and other issues noted on original Airplay. Low latency mode is designed to negate this issues. Apple Music app uses low latency and therefore is always AAC to an Airplay 2 client. Qobuz is opposite and uses Realtime.
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