Hi
Recently acquired a NAIT XS3 and noticed a problem with the unit rattling when gently tapping the case. After some investigation I think I got it narrowed down to be the DIN board that’s loose (if i secure the DIN contacts the rattle stops). Thus creating the rattle, the unit is working perfectly fine otherwise.
The board on which the DIN sockets are located should be free to move slightly as it’s on compliant mounts to reduce the effects of microphony. As such, if you move the unit around then the board can sometimes rattle as the DINs touch the cutouts on the rear of the chassis.