I have an iPod 5.5 gen 64mb board.

It boots up, but won’t play hard disk contents through headphones which are good.

When play button pressed icon in top left corner changes to green arrow but the play timers at the bottom of the screen don’t change left side stays at 0:00.

Connected to computer music plays via itunes without a problem so hard disk must be functioning in that mode.

Headphone jack has been swapped out for known working and hard disk also changed.

Any ideas what the problem could be?