Are you on Android? I had a similar problem with my Pixel 2 last year, and I've seen other Android users report similar issues with other bluetooth headsets.

Are you on Android? I had a similar problem with my Pixel 2 last year, and I've seen other Android users report similar issues with other bluetooth headsets. Under Android developer options, there's an option called "absolute volume" that you can disable which should increase/remove the volume cap on your bluetooth device.