Have some Bluetooth earmuffs/ear protectors/defenders/whatever you call them. They're nothing fancy, but they work, they're comfortable, and I can listen to music while mowing the lawn. Unfortunately, one of the plastic arms snapped; 3D printing to the rescue. The part works well enough that I printed a second one for symmetry.

NOTE: the SCAD requires a relatively recent version of OpenSCAD supporting the angle parameter on rotate_extrude().