Apple has filed a new patent application describing a wireless headset with the ability to play music on its own while the external device is not being used. The drawings show a headset similar to Apple’s prior iPhone Bluetooth Headset, but with a port on the rear that can be connected to a cord or strap with a similar, iPod-style earbud on the opposite side for stereo sound. Proposed features of the device would include the ability to be used…