A headset can include a cable structure connecting non-cable components such as jacks and headphones. The cable structure can be constructed using a molding process. Different approaches can be used to ensure that a conductor bundle extending through the cable structure remains centered within the cable structure during the molding process. A movable tube can be placed in the mold such that the conductor bundle is retained within the tube. As material is injected into the mold and reaches the tube, the tube can be displaced and progressively removed from the mold. Alternatively, the movable tube can be constructed such that the tube may combine with injected material to form a shell of the cable structure. Gates from which material is provided in the mold can be positioned and controlled to facilitate the injection of material in the mold while maintaining the centered position of the conductor bundle.