I accidentally stepped onto my headphone volume knob and shattered it, so I printed a replacement. No clue if it will fit yours, but FreeCAD file is attached, so you can use it to adjust dimensions.

Use small bits of any 1.75mm filament as pins connecting the two halves - push the filament into the holes in the larger part, then snip it about 2mm above the surface.

Print flat side down - even minuscule elephant foot will make pushing the filament into the holes near impossible.