stbiggles

As a complete newbie to Debut I'm sure this question has been asked before but I have yet to find a solution that really works for me. I am trying to record live sports streaming but the video is very jerky. I have reduced frame rate to 15x per sec and reduced capture size to TV wide but that seemed to make little difference. Fast capture seems to improve things but for a 90 minute game the file size would me massive. Can anybody offer some advise please?