Grabby, grabster, digitizer, USB video converter, it carries a lot of names. It could well be that you have connected via s-video, instead of composite, which can lead to this. Also, have you got the correct setting for your video player? Make sure you do not have Pal set when you need NTSC, or vice versa.
Open the program, and under File, Settings, Program settings check that it's correct.
Put the 'grabby' in and proceed to make a recording (IMPORT), on the first page choose composite, and make sure you connected that as well, proceed to next window. Click on 'advanced view', choose Video Standard, and make sure you got the right standard.