Loud snapping from front diff?

Was doing some crawling over rocks and rough terrain. Running it in low gear and 4wd. Had a few spots where I had to get on it pretty hard, and the car would be bouncing, where it would lose traction and then gain traction pretty hard. Noticed a couple times a loud snapping noise, seemed to be coming from the front end drivers side. Anyone else experience this? Put quite a few laps on my track after, and nothing seems to be wrong. Let me know what ya think.

Thx.