Set Timecode to 0 in Final Cut Pro X

Hi. I've inserted my timecode at 38 seconds into my project, but I need it to start at 00:00:00:00. Right now, it's starting at 38 seconds which isn't right for what I'm doing. I've tried changing the timecode base from project to source, but then it starts the timecode at 01:00:00:00 which is still wrong because that means one hour has already passed.

Any help greatly appreciated.