video being randomly skipped (case 6812)

[ggcanna]

I'm running an experiment which involves presenting a series of video and STRT during presentation. The design is: 2 short practice videos (< 1 min) at the beginning, followed by 4 experiment videos: stm1, stm2, stm3, stm4 (length ranging from 7 to 10 minutes) in this exact order. There is a black screen (with "continue" button on the bottom) inserted between every two adjacent videos. What happened sometimes in the experiment is that after showing the two practice clips, medialab went straight to stm2 and started showing from there through stm4 while the entire first video (stm1) was skipped. We are using 6 laptops for this experiment and although this problem has affected 5 up to today, it's never consistently associated with any one of them. At one time, medialab is performing fine with the presentation on all laptops; at another time, one laptop will give me trouble by skipping a video and at yet another time, the same problem will occur to a different laptop. It also seems random as to which video the program chooses to skip. Most of the time it was the first video, but I have had two incidents when the third video (stm3) was missed, one incident when the last video (stm4) was missed, and another incident when both stm1 and stm3 were skipped during presentation. Any idea about what might be going on? Our Medialab is the 2006 version. Thank you very much in advance!