If your guitar that was once quiet has something loose in the neck or headstock this is only caused by dryness as when woods get dry they contract but metal parts do not. We have more about dryness on our humidity page at https://zagerguitar.com/humidity-and-your-guitar/ The most common things to rattle on the neck when woods get dry are the washers on the tuning gears so if you're getting a jangle, when it happens grab each of the tuning are as there's a washer that will jangle when the tuners get loose. If it changes when you touch a particular tuning gear you'll probably notice the loose washer. Hand tighten and you should have no further problems.   Jangling or loose parts inside the neck involve the truss rod which can loosen as well which is only caused by dryness. If you have a loose truss rod, by simply turning the truss using your truss key left or right should tighten it to remove any jangling. Beyond this you would need to hydrate your woods which is addressed on our humidity page https://zagerguitar.com/humidity-and-your-guitar/