It is Mac only.

https://www.sync-mac.com/ It is not free, but worth it, IMHO.

SyncMate works very well on Mac, both for Sonys and A&Ks. It preserves the folder structure and syncs whatever has changed.

Yes Windows 10 using jRiver's Media Center works great for synchronizing with KANN. Unfortunately, that is not the case with Mac. On the other topic, disappointed with KANN that the Play/Stop button does not work with screen off. Great player otherwise.

Thank you, but that page links to Android File Transfer, which I am already using and which requires renaming the files. That page also mentions "attached guide in pdf.4" which I cannot locate. How do you sync, manually or with a tool?

How do you synchronize your files between Mac and KANN? I do not use iTunes but have my FLAC files organized in folders. Currently, I am copying/synchronizing by hand using Android File Transfer. This means, unfortunately, that I need to modify many filenames (remove '?', replace " with ' ). Thanks.

Quote:   I am using HD600 via International and Green Line balanced cable. You need a balanced cable that connects to HD650/HD600 and has a Mini 4 Pin Balanced plug on the other end.

Have been listening to AK100 with IEMs (IE80, SE425, W4R) and over-the-ears (HD25II, B&W P5). My favorite so far is W4R with Shure's large foam tips. IEMs are inconvenient when isolation is not desired.   Listening via ALO International and HD600 with balanced cables is my favorite...

I am using 2 x 64Gb cards (SanDisk Ultra 64 GB MicroSDXC Class 10 UHS-1) without any problems. I write them outside the AK100 and do a manual library scan.

I remember reading in several posts that max volume on AK100 is practically as good as line-out. 

Quote:     I have found SunCloud Microfiber Sunglass Pouch (REI) to do quite well as protection for AK100. It protects agains scratches and can be used for cleaning it.

I love my AK100, it fulfills a bunch of my requirements:   - Excellent sound. - Charged via micro USB (I always have a USB charger and cable handy). - Physical buttons to control volume and play. - Small and long battery life. - Able to browse CDs by folders. - Play 96/24 files  ...