When using the LX in balanced output with turbo mode enabled and high gain, if I listen for hiss I can hear it but it's not something I usually notice when listening to music. As has been said before you will not hear it with most music but it becomes more apparent with classical. Many recordings already contain hiss though so mostly what I'm hearing is part of the recording and not some extra hiss.
Balanced output, turbo mode and high gain is what I use to drive my D8000 Pro planar full sized HPs, and I can turn up the volume up to about 48% before it becomes too loud. Are you sure you are using your player the way it is supposed to be used with a 14 ohm 102 dB IEM?