Bang/thunk when applying handbrake

[GCole]

I'm trying to sort out a noise from the rear axle when I apply just the handbrake and the Jeep is moving. It is a 97 5-speed and all stock. It is a pretty significant bang from inside the cabin and it is definitely coming from the rear, but it only happens with the handbrake. No noise or issues when using the pedal, so it seems like the hydraulic aspect of the system is working properly. It also only happens when the Jeep is moving forward. If I am moving in reverse, no noise. It looks like the cable adjuster in the center of the vehicle is moving smoothly (video down below). I even pulled the diff cover and everything looks normal inside there (c-clips engaged, nothing in the gear oil). Driveshaft and u-joints look normal as well, no excessive play or anything like that. I rebuilt the drums when I regeared the axle about a year and a half ago, so new hardware went in then. Ring and pinion backlash feels similar to when I installed the gears. Would love some ideas of what else to check around.

Thanks!

https://photos.app.goo.gl/twaPZQEpksCRsvhb9

 

[GCole]

And since I was already into the differential, I went ahead and pulled the driveshaft on the passenger side since that is where it seams to be coming from. Nothing of note to my eyes, but maybe someone with more knowledge will see something. The zip tie in the background isn't permanent, I just placed that to keep the parking brake cable a little further away from the control arm to make sure it wasn't rubbing somehow.