Problems in video output of a show may be due to various reasons based on the show configuration:
If video output keeps freezing at the same location ...check whether there is enough storage capacity. See also Error during video creation.
If video output freezes mainly during the transitions or at the end of a video ... your videos may not be entirely ok; the data may be defective or incomplete.
Solution: In the function bar, click 
Display log file and take a look whether
there are any entries such as "Frame not found". In such a case,
open the video file properties in the Media Pool and enter a value between
2 and 5 frames
next to Missing end frames.
Should the problem come up again during rendering, you can increase this
value further. See also Video
Properties.