Cannot Sync All Songs In My iTunes Library to My iPhone 6 and iPad Air 2

Question

I have over 10,000 songs in my iTunes library--about 7,000 are songs I ripped from CDs and about 3000 are songs purchased through the iTunes store.  I am able to sync all the songs to my iPod Classic without any problem.  However, only about 7,000 songs are synced to my iPhone 6 and iPad Air 2--a mix of all the songs purchased and some of the songs ripped.  How can I get my complete library synced to the iPhone and iPad, both of which are 128 GB and have plenty of room for the songs.

Answer 1

Launch the Console application in any of the following ways:
☞ Enter the first few letters of its name into a Spotlight search. Select it in the results (it should be at the top.)
☞ In the Finder, select Go ▹ Utilities from the menu bar, or press the key combination shift-command-U. The application is in the folder that opens.
☞ Open LaunchPad. Click Utilities, then Console in the icon grid.
The title of the Console window should be All Messages. If it isn't, select
          SYSTEM LOG QUERIES ▹ All Messages
from the log list on the left. If you don't see that list, select
          View ▹ Show Log List
from the menu bar at the top of the screen. Click the Clear Display icon in the toolbar. Then take one of the actions that you're having trouble with. Select any messages that appear in the Console window. Copy them to the Clipboard by pressing the key combination command-C. Paste into a reply to this message by pressing command-V.
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