Grapher and 3D Quicktime Movie Bug

Exporting a movie of an animated three-dimensional (3D) function (e.g. z=sin(ax)+cos(ay)) with Grapher 2.6 results in a *.mov file that, when opened in QuickTime Player Version 10.4 (928), shows only one frame for a certain while and then ends on a blank view. The same movie freezes VLC (Version 2.2.6 Umbrella, Intel 64bit) upon opening. It seems that the internal structure of the *.mov is broken... Anybody has any insights?