I have 1708 songs checked in my iTunes that should sync to my phone, but only 793 actually sync (even after a restore). What is going on, and how can it be fixed?
It could be a variety of things. Songs might be incorrect format or too high of quality for starters. Do you get any sort of error message when you sync? Look through the info of the songs that aren't syncing and see if you see some sort of pattern.
I had all my songs on my phone since I got it for Christmas, then one day it synced and it only had 793 songs on it. No error comes up when I sync. When it first happened, my iPhone Summary tab said there were 1708 songs on my phone when there wasn't, but now it says 793 even though I have 1708 songs checked.
I found that if you went into the "On this iPhone" tab in iTunes they files would show up, so iTunes thinks they're already there! If you select "manually manage music and video", go onto the" On this iPhone" tab and delete the files iTunes won't think they're on the phone. Then manually dragging the files onto the phone forced them to sync. Just turn off manually manage music, and all will be sorted! This worked on my 4S.