My itunes won't let me sync some songs onto my iphone 4s?

I want to add music to my phone but everytime i go to sync it only half the songs i go to sync, sync! I have like 78 machine gun kelly songs 30 waka songs and 80 wiz songs and only one of my waka songs sings and half of all the other songs i even deleted them all and tried to sync them again and it didn't work and i i tried to manually add them and i also synced my entire library and nothing works. Please help!

Added (1). I also do have enough free space. I have about 3.5 GB left which is enough space and my computer is authorized

Restoring my Jailbroken iPhone 4s?

Hi. I'm trying to un-jailbreak my phone that is running on 5.1.1. I tired to restore it but it says it could not be done due to Error: 3194. Can you please help? I'd like to update my software to iOS: 6.1 since it just came out and I'm so far behind.

Is 500mb enough data on an iPhone 5?

I get 500mb of data and 1GB when I'm connected to a Wi-Fi. Will this be enough on the iPhone 5? I don't want to download anything I just like to use Facebook and twitter a lot.

Iphone 5 or Samsung Note 1 or 2?

Which phone should I get iphone 5 or Samsung Note 1 or 2 I can't decide. I've read a lot and almost everything on the Samsung Note 1 is better than the Iphone 4s but I don't know which to chose please give a descriptive option and why thanks.

How to update iOS using cellular data network?

My uncle's using iPhone 3G and he wants to update his iOS to version 6 from version 5.1 but the problem is, the update is asking for a Wi-Fi connection whereas he just updated his iPad 3 to iOS 6 using cellular connection. Anyone have any idea

Added (1). It's an iPhone 3GS, my bad. So he's getting the option to update but only with Wi-Fi.

My iPhone won't play music with my apple headphones?

My apple headphones work on my iPod but not my iPhone. And my non apple headphones work on my iPhone. What the hell?
I tried restating my phone but it still doesn't work. I know my headphones work cause I can listen on my iPod.
Has this happened to you/how do I fix it?

Sending pictures on my iphone?

I was wondering if someone could help. I just bought a new i phone and i'm a bit of an iphone noob. I have all you can eat data roaming and unlimited texts. Is it free for me therefore to send pictures to people?

Added (1). What about if its to another iphone via imessages? (i don't really understand imessage but i'm under the impression its if your connected to the internet and between 2 iphones)