Characters with AIPath freakout and stop following path after some collisions

I am having an issue where my characters will stop moving towards the target after a collision. It seems like they are still trying and they still are repathing. Sometimes they figure it out, other times I need to either turn off the ability to move or change the target such that they would have to turn around to reach it. The characters have a rigidbody, no controllers.

I have a small video of it uploaded here It’s a flash video(swf), sorry, converting it to a GIF either wrecked formatting or turned it into a 400MB GIF

In the video I am dragging the target around. Notice how they are mostly fine for the first 18 seconds, then in the bottom left after some collisions one of them gets stuck and just shakes. It takes me moving the target behind him to get him to work again. When I add more units then the issue gets much worse, often near the target as they run into other characters.

My guess is that this has something to do with the rotation of the object, I am not sure though. I tried to set the rotation differently however was running into some errors and haven’t gotten it to successfully work.

Any suggestions for what to check to get this worked out?

I am not sure what could be causing that. Does it work if you remove the rigidbody and attach a character controller instead?