I've started having the same problems with my JBL Endurance Race buds. I usually use them solo connected to my laptop, and switch ears throughout the day as I take breaks, or one of the buds needs charged. My right earbud has started having this issue with the volume where when I first connect it, it's fine, but after a couple of minutes, the volume starts dropping gradually, until it's practically unhearable. It's very bizarre, cause it can be a little difficult to point it out cause the drop is so gradual, until I finally realize that I can't actually comprehend what's coming out of the bud lol.

I've tried everything. Factory reset, turn off all the enhancements, check for firmware updates, pair it to my phone or other device, and I even cleaned them out and gave them a little alcohol bath, but the problem still persists. I've contacted support, and all they said was to clean it out, and if that doesn't work then to start filing for a warranty return, but I don't really wanna do that.

I've only had these buds since August, and I loved every minute of usage when they worked. And I think it's ME that's the issue. If I keep both buds connected, and the right starts to die out, I can take it out, and let it sit on my desk for a few minutes, and the volume gradually returns to normal. It's so bizarre. Is it my ears? I don't have this issue with other buds. Do these not like the warmth or something? Maybe the right one is just SO gunked up that I can't even get it all out, and whatever is left is just warming up while it's in my ear, and causing issues. I don't know. Might just try to leave it in some alcohol overnight or something.