problem with a Canon Powershot SD600.

Video works fine on the camera, but when I plug it through the Canon Camera-to-USB cord it can connect to the Zoom Browser software and download the file. Trouble is, when I play the video on my computer the Video has a strobe light effect (dropped frames?). Audio works fine, but the video is slow and off (same video/audio playback fine on camera).

-I tried dropping straight into MYCOMPUTER but windows media and quicktime could not play file.
-I will try USB port in the back when I get home, but why would that differ from front USB port?

Any other recommendations? Where are the upload settings for FPS?