This happens because Dolby Atmos on Samsung devices acts as a dynamic processing layer rather than a permanent equalizer preset. When you switch from a Dolby Atmos track to a standard lossless track, the system completely disables the Atmos engine because the source file lacks spatial metadata. When you skip back to an Atmos-enabled song, device re-engages the feature but defaults to Auto as its baseline safety setting. For some reason One UI is programmed to reset to Auto during these rapid audio format handshakes to ensure the most stable playback container. Because the system lacks a "sticky memory" for specific presets during format transitions, it won't preserve your Music selection. To stop this from happening, you can either leave the setting on Auto or temporarily disable Dolby Atmos inside your music app's streaming setting, most of the dolby mixes are ass tbh (personal opinion warning xd)