This is a simple two color splice of Jeroen Hustings' Headphone Stand: https://www.myminifactory.com/object/headphone-stand-42603.
The headphone rest piece can be downloaded from Jeroen's original version.
My prints resulted in noticeable edges from my extruded splines, as well as a small defect showing a thin line in the middle from the alignment pieces.
Also, you can see white blemishes on the black prints due to untreated sanding.
The notches are really only for alignment. I used superglue for assembly.
STEP file included.