Answer to "How do I fix my iPod Touch earphone jack?"The skins may prevent the jack from seating properly, try them without the skin.
Answer to "A bluetoot headset that works for an iPod Touch and PDA simotaniously?"Apple has disabled the bluetooth stack on their devices. There isn't much one can do with them except connect to a headset. On other devices, one can set up a personal area network (PAN, BTPAN). This would allow multiple devices to communicate simultaneously.