I have my wife's iTunes library on a NAS device because it was taking too much space on her laptop. I didn't trash the old iTunes library in case we ran into trouble which I think we did. I noticed when I got on her laptop today that the NAS share was not mapped to her computer. I rebooted it and the share was back. I compared both iTunes library folder sizes and the one on the NAS is smaller than the one on the laptop. Does that mean we are missing songs? How can I check for missing songs, etc? we have iTunes Match and Apple Music.