Crossfade should work fine on the X5.

For example, go into the menus: Settings > General Settings > Playback >
Crossfade, then set the 6 options to be as follows:

Enable Crossfade: Always (or Shuffle and Track Skip)
Fade-In Delay: 0 s
Fade-In Duration: 1s
Fade-Out Delay: 1s
Fade-Out Duration: 2s
Fade-Out Mode: Crossfade

Then play a track, skip to next track and you should hear the tracks
crossfade.

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pondlife