Buzz/rattle and humidity changes?

[tornadobass]

My new bass, a carved Romanian labeled Matthias Kriner, has an on-again-off-again buzz/rattle, especially with pizz. It seemed to get worse when the humidity indoors was in the low 30% range.

With some rainy weather this week, the indoor humidity has gone up to the mid 50% range and the buzz/rattle is gone. The shop I got the bass from gave me a six month warranty in case the noise came back again.

We might not get below 40% humidity until the heating season starts up again in the fall.

How do you find a noise to fix it in this situation? Or is the way it comes and goes a good hint about the nature of the problem?

[Eric Hochberg]

I'm no luthier, but when the humidity goes up, the wood swells and a crack or separation may tighten up.

[Square Bear]

maybe a seam is coming open? not uncommon, take a close look and you should probably take it to a luthier.