NaN values for particle tracing using brownian motion

Hi, I was wondering if anyone had experienced this problem and/or knows of a fix:

I have a very simple model involving 3D steady-state laminar flow through a rectangular channel with symmetry sidewall conditions (this is a simplified version of a more complex domain). I am using the particle tracing for fluid flow module (along with the drag and brownian force) to track particles through the domain, where one of the walls capture the particles via the Freeze condition. I would like to obtain the positions where each particle "sticks" to both the outlet and the wall condition - the qx, qy, and qz positions of each particle would be sufficient.

The problem is that, when including the brownian force, the positions of the immobilized particles register as NaN. I can plot the positions of these particles just fine (3D plot group, particle trajectories), so I believe the particle positions exist somewhere within COMSOL. I get the NaN values either trying to export to a table or exporting the data set.

When disabling the brownian force, the particle positions are as normal.

Is there any way of obtaining the particle position data other than qx, qy, and qz?

The simple model is attached here.

Thanks for your help,

Nicholas