I don't know what is the problem, but I've never have been able to get any smooth playback with large Quicktime movies. DivX AVI-files play fast and DVD's (almost) perfectly smooth on my old P3 600 MHz with an old Geforce 1. But not Quicktime, so I usually avoid the format, despite it's cross-platform capabilities.
But AVI-DivX and XVid also play on Mac's and Linux-PC's, so that is pretty cross-platform if you ask me.
--- stefan boeykens --- bim-expert-architect-engineer-musician ---
Archicad28/Revit2024/Rhino8/Solibri/Zoom
MBP2023:14"M2MAX/Sequoia+Win11
Archicad-user since 1998
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