iPhone 6 Plus w/iOS 10 PB 4 can't sync with iTunes

[tokenmacdude]

Aloha everyone,

I am running macOS Sierra PB (16A294a) and iTunes 12.5.0.68 on my rMBP, and iOS 10 PB 4 (14A5335b) on my iPhone 6 Plus. I didn't have this issue until today, but when I attempt to sync my iPhone, I get an error message stating that there is not enough room on my iPhone, although I'm showing 51.9GB free (48.40GB free according to iTunes) as shown in the attached screenshot.

Has anyone else run into this issue? I plan on upgrading to iOS 10 PB 5 after I get home from work and hope to not see that error message again.

 

[Shirasaki]

If you attempt to sync too much stuff on your device you will receive this error.
The only way to fix is to reduce the content you want to sync to your device.
However if what you want to sync is not exceeding free space then it is weird.

 

[tokenmacdude]

Thanks for your response. It is the latter, which is why I posed the query. I've upgraded to iOS 10 PB 5, so I'll try again today. I'll post screens from both my rMBP and iPhone if this issue persists.
[doublepost=1471631138][/doublepost]Unfortunately, the same behavior presented, even after upgrading to iOS 10 PB 5. I've submitted feedback to Apple. Here are the screenshots I took from my iPhone and my rMBP. Keep in mind that I'm only plugging my iPhone into my rMBP to charge it while at work. I've not added anything to the content that was previously successfully synced, which is why I don't understand my inability to sync my iPhone with my rMBP. One other thing to note is that my iTunes library is housed on an external HDD.




EDIT: I checked the "On My Device" section of iTunes, and there is a huge discrepancy between what is listed there and what is actually on my iPhone. If you look at the bar on the bottom, I should have 49.88GB of audio on my iPhone, but only one song is listed. None of my ringtones are listed, even though all are being synced. This version of iTunes appears to be the culprit, but I'm not sure how to work around it.

 

[Shirasaki]

If you look at the bar on the bottom, I should have 49.88GB of audio on my iPhone, but only one song is listed. None of my ringtones are listed, even though all are being synced.

I am still thinking possible reasons but Apple does not treat ringtone separately. They are counted as songs.
The huge discrepancy between iTunes and device regarding available storage is an old issue starting from iTunes 12. I can see a whopping 4GB difference for apparently no reason.

 

[tokenmacdude]

Aloha again everyone,

For whatever reason, I had to unsync my music (which deleted everything from my iPhone), then resync my music, and now everything is good to go. Everything matches up as well in the "On My Device" section of iTunes.