I recently switched from Windows to MacOS, and it seems that there is no way to synchronise music with my 970 on my MacBook Air. I have a ‘Running’ playlist, and after a variable number between 1 and about 30, I get an error and can no longer synchronise. I've tried changing the cable and reinstalling Garmin Express, but none of the most likely options work. The same thing happened with Windows, but at least it worked sometimes, and this has been going on for several years. Is it possible that this issue cannot be resolved? The solution I will adopt is to mount the Garmin as an external drive (as I did with Windows) and copy my favourite songs ‘manually’, but I am amazed that a company like Garmin is unable to address and resolve this issue. Just to be clear, I am a very advanced user and have been a senior programmer for several years, so I am capable of going beyond the usual trivial solutions. In the end, I think I will write a script that will read the songs in my playlist and synchronise or copy them to the Garmin.