I'm using an Iphone 5 on Ios 9.1. On two occasions a couple of weeks apart, I've listened to songs on my phone ripped and synced through Itunes, and they've started playing without the vocal part. The first time, it solved it self, but today it just didn't work. No vocals at all. Feels like I'm riding the karaoke taxi. The songs have worked for many years, so it's kinda strange. These are all Pink Floyd songs, BTW.