Weird problem Wavell 4 pro

Hello, got a pretty weird problem with my wavell 4 pros. Over night one earbud just started to play music much quieter than the other one. Tried looking for common problems but all I got was earwax blockage or firmware problems. The right one still works, if I crank the volume on my phone to max and in settings tell the left bud to play at 50% the sound is relatively equal but in lower volumes it feels like the right is still lower. Is it a hardware problem or what seems to be the issue?

I have tried most things, next is probably to try to open them up but I guess there is no going back from that.