Only occasionally see bluetooth volume slider, when changing the volume from my bluetooth earbuds

[anon(8453378)]

I have Jaybird X2 earbuds paired with my Verizon Galaxy S5, android v5.0. I have been using the earbuds for 6 months, with no problems. When I change the volume from the earbuds, it changes the volume on the buds, but not the phone's system volume (phone and accessory's volume are separate). On a few occasions though, changing the volume from the earbuds, brings up a bluetooth volume slider popup on the phone. It looks like the regular volume slider, except that it only includes the bluetooth specific vol slider. Any ideas why this only occurs occasionally (might have noticed it 3 or 4 times over the course of 6 months)? I like the idea of the volume controls linked for bluetooth, but from what I see online, this isn't available until android v6.0.1. Thanks.

 

[anon(8453378)]

Wondering if anyone else has noticed the bluetooth volume slider, when adjusting the volume from their bluetooth connected accessory.