Conventional stereo audio material is often produced using amplitude panning techniques to achieve flexible positioning of sound sources with a limited number of loudspeakers. Consequently, for faithful playback the orientation and position of the listener are very restricted. If stereo audio is reproduced over virtual loudspeakers on headphones incorporating headtracking, these position and orientation restrictions limit the realism and spatial accuracy of the reproduction. In this paper, it will be outlined that amplitude panning and the corresponding phantom sound sources cause spatial quality limitations for headphone rendering. A novel method to circumvent phantom imaging on headphones is presented and evaluated in a listening test.