I just noticed a folder with .m4a files (music) that does not show up in the library - the folder shows up, but not the files.

.m4a files must be a rare music format.

in the Fopnu library, right click the folder that contains the m4a files and go to file types and select other (make sure audio is selected as well). that should let those files be shared.

Got it, thank you.


It is AAC from iTunes.  Just for interest sake:

Format                         : MPEG-4
Format profile                 : Apple audio with iTunes info
Codec ID                       : M4A  (M4A /mp42/isom)
Overall bit rate mode          : Variable
Overall bit rate               : 267 kb/s
Encoded date                   : UTC 2013-09-30 16:49:01
Tagged date                    : UTC 2013-10-02 14:15:06
Writing application            : iTunes 11.1
Encoding Params                : (Binary)

Audio
ID                             : 1
Format                         : AAC LC
Format/Info                    : Advanced Audio Codec Low Complexity
Codec ID                       : mp4a-40-2
Duration                       : 4 min 21 s
Bit rate mode                  : Variable
Bit rate                       : 256 kb/s
Maximum bit rate               : 339 kb/s
Channel(s)                     : 2 channels
Channel layout                 : L R
Sampling rate                  : 44.1 kHz
Frame rate                     : 43.066 FPS (1024 SPF)
Compression mode               : Lossy

I may be wrong but I seem to remember that the itunes files are DRM laden

I would caution against sharing such files as the metadata contained within them is traceable back to the original purchaser.