Photos: Slideshow exported to video is choppy
Just upgraded to Mac OS 10.10.3 with the new Photos app. I tried to export a "Magazine" theme Slideshow as an .m4v video file with the Photos app, but the video playback is choppy. The slideshow is a combination of still shots and videos. It used to work fine on this same iMac with iPhoto before the upgrade.
iMac, OS X Yosemite (10.10.3), iMac (early 2008) 2.8 GHz Core 2Duo, 4GB RAM