avicap error

Hi, I found an avicap example at http://www.codeproject.com/audio/avicapwrp.asp but i have a strange error. When i restart/start my computer (on Win XP) and i run the program (the one in VC++ with video source - composite) the image is with many vertical lines and you can''t see anything clear. After i close the program and i start the TV tuner program with video source composite and i close it and then run the program again(this one in visual c++) the image is cristal clear. WHY? I tried even with DirectShow and i got the same error. Can someone explain me how to resolv this problem. Thanks.