Reply to Kontrol S4 issue....

Having an issue getting itunes music from Macbook Pro into the software for the s4. Some of the music will play. But most will not. For example, recent downloads from ZipDJ site are not loading. They show up in itunes and play just fine in there. Once I try to hook up the S4...no dice. I checked the manual and tried adding another directory thru file management where the music is located but not having any luck. Any info is appreciated.