are you using some type of ipod extension cable?  if so, keep in mind that almost all of these cables only extend a few of the pins of the ipod and not all 30 pins like you would need for full functionaility of the psx2.

when I need to hide the psx2 away, i use this unit from mbquart:

[Link: mbquartnautic.com]

and this cable to extend the connection from the psx2 to the mbquart
[Link: cablejive.com]

you are limited to 2' or 6' with this solution.