Has anyone with a Series 3 and Series 4 noticed music playback on the AW4 sounds a bit flat compared to the AW3? I've tried two different sets of headphones (AirPods and Bose Soundsport). It's very subtle, but playback on the AW3 defintely has a richer sound. For testing, all songs were played directly from the watches (i.e. no streaming) at the same volume level. I'm not aware of any way to modify AW music playback settings other than the volume but would love to hear any suggestions.