A:AnswerYou can but you would not want the speakers to be in the same room, the speakers connected via Bluetooth will lag behind the speakers that are wired.
A:AnswerI don't know the cartridge number it comes with, it's white. But there is only one different one available, it's an elliptical. I switched to this and it greatly improved the sound quality. The replacement # is ATN2600LE. Costs about $50