@Andrew-Dickerson
Could it be that you are using certain characters in your file which afren't recognized by your navigation device?
I do know that Windows has a somehow a limitation of 255 characters in file names. And it doesn't accept some rarely used characters in a file name.
I have the experience that Windows cuts off file names when it is too long or it has some characters in the file name.
Not sure though if this will help you.