i don't know what's going on. i've never had this problem. but, when i hit play, vegas only plays like 15 frames, then starts over again. it's like it's stuck in a loop.
i can't find any settings to correct, and i've tried on multiple video clips.
You have a small selection area set and playback looping turned on. Either clear the selection area OR unclick the looping button to the left of the play button.