screen capture frame advance

[mhoople]

Every 6-12 months I ask this question. I've asked some other ones that people who know a lot about the inner workings of smplayer could answer. I would have never been able to figure them out by myself. So I'll ask again.
On my main computer when I press the hotkey for screen capture sometimes it will allow me to advance frame by frame for as long as I want. However, about half the time it will only advance 3 frames and then I have to hit the space bar and it will advance up to 3 more. My older computer has smplayer on it and never had this problem. I feel like there must be some setting in there that causes this. Any suggestions would be appreciated. Thanks