I have tried both the versions, and they both have this bug. With Hi-res output active, audio is slightly audible at very high volume levels. Also, the Equaliser amd Tone when enabled, distorts the audio. And the volume level changes to hundred everytime I change any setting in the Audio>output. V704 worked perfect for me, all settings kept the same. Most of my tracks are 24/192 flac files.
Samsung Galaxy S6
Android 7.0