Ipod over capacity

I recently got a new computer and used itunes match to transfer my entire library. This entire library, over 2100 songs, was all on my 16GB ipod nano previously. Not all of the songs would transfer and I even got rid of some, leaving me with around 1800 songs. Now my ipod won't sync. I get an error message stating that I don't have enough space to sync my library, but I had even more than that stored previously. I tried restoring it to factory settings. I also checked the "other" usage but it is only 56.2 MB. Why is it that I can't sync 1800 songs when I previously had over 2100?