I recently started having a problem watching my video in the preview window in AE. The video plays, but only up to a certain point and then it jumps back to the beginning of the video and I can't watch the rest of the video.
Maybe someone has an idea what it could be that this is not working properly?
It's working correctly because AE can only cache so much data for a RAM preview or playback from the disk cache when native realtime playback is not available. Since you don't even seem to be aware of this I would strongly urge you to read the online help on these basics.