Premiere Pro 15.0: exported .mp4 video hangs in the last few seconds of playback

Just upgraded to 15.0 and it seems like the H.264 container is broken across your products. Videos export fine from Premiere, but the exported .mp4 video hangs in the last few seconds of playback. I tried deleting media cache, moving the 14.9 sequence to a new project, new sequence, the works. I even tried exporting as a QT 422 .mov and then converting that to H.264 in Media Encoder 15.0. The .mov plays perfectly all the way to the end. But the converted .mp4 from Media Encoder using that perfectly playing .mov file also hangs at the end of playback, same as the Premiere-produced file. I've also tried to queue from Premiere to ME to export with the same hanging results. Any insight?