Depending on your selected audio device in FL Studio's Audio Settings, you may experience issues with jittery playback or song position jumping to an incorrect location in the Playlist Timeline. This is generally caused by the audio driver not reporting the proper playback position.
If you encounter such behavior you can correct the issue using the following steps:
1. Within FL Studio select 'Options > Audio Settings'.
2. Change the Playback Tracking option to 'Mixer' instead of 'Driver'.
Image-Line Support Team