Final Cut Pro X - version 10.6.8 (FCPX) no sound issue

First off - I've got an old system. A 2015 MBP and FCPX version 1.6.8.

I have an iPhone 7. I shot video from the iPhone 7 and then imported into FCPX - as I've done for the past 8 years.

When playing a clip in the Browser window I hear no sound at all. But, there is sound in the audio clip. I can drag the same clip to the Timeline and hear sound.

So what's up? What should I check to get this working?

I'd like to review the clips in the Browser - but I need to hear the audio.

EDIT - AI solved this for me. In the Audio Inspector panel I needed to set "Pan Mode" to Stereo. All of the imported clips had this setting set to "None." I don't really know why. But, anyway, the problem is now solved.