I have this weird issue with my PowerBook (2nd last revision) for quite a while; whenever I plug my iPod headphones in I only hear audio on either the left or the right side. When I then go to the audio panel the audio balance is also to the left or the right. When I center it the audio is fine. However, when I plug again the headphones in at a later stage the audio balance is again off to the left or the right. Is anybody familiair with this issue?