Ipod touch incorrect capacity showing

Question

Hi
I recently re formated my laptop and have re installed itunes.
When I puigged in my Ipod it stated that it was registered to another computer and I would have to register it with this one loosing all of the content, this was not an issue as all of the music, films etc were still on the laptop.
My problems start at this point, my music folder in windows 7 shows as 2.5 Gb approximately with 424 songs, and when imported to iTunes it shows the correct number of tunes, (424 songs) and 2.6 Gb approx.
When I sync the ipod the music then expands to 3.6 Gb but still with 424 songs, there are no duplicates and I have not sync'd any other items like books or films.
Before I had to re register the ipod with this laptop the music showed as the correct 2.6 Gb
Any suggestions as to whats happening here as it is the 8Gb touch every meg is important.
I did try to reset the ipod to factory settings and ensureed it has teh correct software but again still expands 2.6 Gb music to 3.5 Gb,,
Any suggestions appreciated
Andy

Answer 1

You only have 56.6 GB available to you. The difference between that and the 64 GB advertised capacity is taken up by:
The operating system since you can't use that for storage
and how GB is advertised and used/reported by the operating system. See:
How OS X and iOS report storage capacity - Apple Support
The update did not change anything except likely reducing the capacity by 10 or so MB since update typically add things and thus takes more storage for the operating system