My CRM4 also developed a nasty rattle on a gig that was particularly prominent when playing open strings. This results in annoying booming and distorted lower register notes that can be heard even over a 20-piece big band. I immediately changed the battery in the preamp but that wasn't it. I relaxed and tightened the truss rod (to the point of there being no resistance to the turning the nut further) and raised the bridge to eliminate string buzz, yet the rattle persisted. I feared a blown speaker or fried amp but thankfully these were not the issue.
I contacted NS support via the website and received the response below within hours from Greg K at NS Design:
A rattle at the instrument attachment bolt would be exceedingly rare, but it is possible. It can be difficult to locate the source of a rattle, but with the CR Tripod stand it would be more likely that it's the top tube rattling inside the bottom tube. This isn't a common thing, but it has been known to happen.
What you'll want to do is loosen the height adjustment assembly at the midpoint of the stand, shown below circled in red (see Greg's photo attached). The wingnut can be loosened by hand, then the bolt opposite the wingnut can be loosened with an Allen wrench and the clamp can then be removed. Then the top tube can be pulled out of the bottom tube and a couple of layers of electrical tape can be wrapped around the bottom end of the top tube and then the top tube can be reinserted into the bottom tube and the clamp assembly can be reattached.
Based on our experience ... it's likely that by performing the steps above the rattle will be eliminated.
I'm happy to say that Greg's diagnosis of a simple mechanical problem in the tripod itself was accurate and that the electrical tape solution eliminated the rattle entirely. Note that a single layer of electrical tape around the tube was sufficient.
