Boron - USB ->> Particle Serial Monitor hangs

We are running long term testing - days. We use “particle serial monitor” from the workbench on a MAC to monitor the internal details of the application. After several hours the output to the monitor will stop - just hangs in mid line. Serial output via the USB cannot be restarted without first pressing the reset button on the boron. Once this happens, we cannot flash the boron over the USB from the workbench without first pressing the reset button. We are using version 1.5.2 of the OS. The application continues to run - data is published and sent to the host via web hooks.

We run the same application on Electrons and this issues does not happen.

Is there any was an Application can cause this effect?

Open to suggestions.