Replaced axle and now clunking in back

I finally got a rear axle replaced, and all new cones on a new axle… I assembled it back together with 7 or 8 of the bearings in on each side and some grease, put it all back together, put the freewheel cogs on (how did I even try it without the freewheel remover before…) and wheel was spinning fine without play left/right (well, maybe 1mm). The gears all shift too.

When I ride the bike I am often hearing a clunking in the rear though. When I just spin the crank or wheel when the bike is stopped It seems I cannot get it to happen. The back wheel feels pretty good. What should I look at for adjusting this? It happens when freewheeling and when pedaling and I don’t see anything obviously tapping or loose.