Agree. I have all the B&O headphones and never use any of them except A8s for mobile use. I use either Sennheiser HD600s or Grado RS1s. I do use a headphone amplifier and the ones fitted to most devices are an afterthought. I don't know about the one in the BS9000, but the one in the BC2 is dire. I use a Musical Fidelity X-Can V3.