Hi,
Depending on what you call "loud noise", several things may be happening in your system, but most of them will be better explained by the hardware experts in the device forum.
For example, if the "loud noise" is a repeating sound, it means the CPU is halted but the DMA of the DSP is continuously sending the buffer data to the external D/A converter (a CPU halt does not necessarily halt the DMA as well). Given the data is not updated, the sound is continuously repeating itself.
If the "loud noise" is a pop or click, then I suspect the CPU halt causes the data that was being sent to the D/A converter to suffer a sudden variation (as the data flow is interrupted) and therefore the analog circuitry on the Line Out would overshoot. This can cause a pop or a click on the speakers.
Therefore, in my opinion this scenario is to be expected in a sudden halt of the CPU. As I mentioned before, the experts in the device forum would have additional insights and therefore you may want to ask this there.
Regards,
Rafael