I've noticed from the beginning that the AirPods are considerably louder when used with the Series 3 than with any other device. I usually use them at one or two notches from full volume, but on the Series 3 it's closer to 75%. I'm wondering whether this is regulatory? Perhaps Apple Watches don't come under the same rules as phones.
OP ... check on your phone to be sure none of the settings for the Music app for playback were somehow altered. If you Volume Limit is on and set too low the AirPods can be affected too. Mess around with Sound Check too.
gigaguy, I thought you were joking but I just reversed and put the AirPods in upside down...the sound does change. I'm guessing the opening is angling more directly down your ear canal when placed this way.
Not sure I agree they look better this way...buy hey, they are not winning any style competitions anyway.