Which version of iTunes are you using?
What is the iPod software number as shown in the iTunes Summary windows?
If both the soundock and the earphone has no sound after the HardReset, then I think you Audio chip has been fried.
But please try this Hard Reset again
- After charging till full charge, at least 2 hours (preferably 4 hours)
- Toggle the Hold switch, make sure you dont see the red mark when you do the next step
- Reset the iPod -> Press Menu and Center button simultaneously for about 10 secs till the Apple Logo comes ON
- Then release the buttons
- Select your preferred language.
- Test the sound again.
Here is the Apple support Article on the 5Rs
If it doesn't help, try Restore after the above.