Why does my iPhone remove songs after syncing?

It just started today, I woke up and played music in my playlist. After a while I wanted to pick another song, and realized it said 272 songs, instead of my 400 some songs it's always had. I went through and fixed it, from my iTunes on my laptop which hadn't changed, and synced it to make sure it went back. Now at 399 songs, I took my dog for a 30 min.walk, and when I got home checked the playlist, and it went back to exactly 272. I don't have my phone on Wi-Fi either. So I made another playlist altogether and got it back up to 399 songs, and synced it to iTunes via laptop, to save my newly made playlist. And when I unplugged it, it was back to 272 IN THE NEW PLAYLIST.

I would set itunes to manual, thats what I do… Then I just copy what I need etc.

  • Will syncing my new iPhone remove my songs on iTunes? Hi, I just got a new phone and I'm confused! I've got an iPod Touch will over hundreds of songs on my iTunes. If I plug my new iPhone in to the computer, will I be to transfer my iTunes songs on to my phone without it deleting anything? Will this make a difference when I plug my iPod into the computer? Haha I don't know much about phones tbh!
  • Why is my iPhone syncing random songs? So every once in awhile while I'm listening to music on my phone it starts playing some song that is not on any of the playlists i sync to my phone. I've made sure that I didn't accidentally add those songs to the playlists or tell it to sync another playlist, they just randomly show up. Why is this happening?
  • Why aren't my songs from iTunes syncing to my iPhone? I have 1365 songs in my iTunes library which I can play. But only 1260 songs are transferring over to my iPhone. I just got a replacement iPhone about 4 days ago so I'm not sure if that has to do with anything?
  • Why aren't all my songs syncing onto my iPhone? I just got my iPhone last week, and after I synced all my songs (590 of them) to my computer, I tried to sync them onto my iPhone. However, only 345 of them are syncing. In iTunes the box next to "Sync Music" and "Entire Music Library" is checked. Down at the bottom the bar that shows how much music, apps, photos, etc.shows that I have 590 songs, but once I click "Apply" it syncs, but the bar reduces to only 345 songs!