I have an iMac, with the latest OS-X, running Adobe Lightroom CC, also up to the minute.
when I create a slideshow and ask it to sync slides to music, it stalls before completing the task. I can cancel, but that's not helping much.
it does work if I turn sync off and use the fit to music button... but that again isn't sync to music is it?
I have tried this with a small number of slides (9) and with other slide sets. Same trouble persists. The music I've tried is off my hard drive, both M4A and MP3.
Did anyone have an answer for this? I have the same issue on my PC.
Sorry, I've not tried to do this in quite a while.
Other problems I've had with the slide show were solved by selecting a template in the slide show module (left side) first. That seemed to settle things, at least until you shut down LR.
Hope that helps.