Nudging clips by subframes in Final Cut Pro for optimal sync

I recorded a musical performance from two different perspectives and want to alternate views seamlessly cross fading their audio tracks as well as video tracks but one iPhone's 30fps footage needs to be advanced by less than a full frame to keep the audio and video from each iPhone in optimal sync.

[Re-Titled by Moderator]

Original Title: in FCP, can clips be nudged by subframes for optimal sync with another clip? I have selected time code to include subframes but trimming or sliding clips seems to be limited to frame divisions.