I installed a bone saddle into my L-04 last summer and it has been sweet ever since....until now. The last week or two I started to hear a rattle/buzz like sound coming from the body of the guitar so I started to wonder if a brace had come loose, even though it has been properly humidified. I changed the strings tonight and while all the strings were out a tapped the top looking for the rattle and rattle it did. But once I took the saddle out, the rattle stopped.  So it has to be the saddle moving around in the bridge.
  The thing is, why after almost year does it start moving around now?

The bone saddle is stable.  The ebony bridge, however, will expand and contract causing the saddle to be either too loose or too tight.  Too tight is really bad because the bridge can crack.

What are you using to humidify?  Do you have a hygrometer?  It sounds like the guitar has dried out and it needs more humidity.  The bone doesn't change w/ humidity levels but the bridge does.

I'd agree. I don't think the saddle shrunk. I'm also wondering though about test. It seems to me that bone would have to loosen a fair amount to cause rattle because of all the downward pressure on it. With the strings off, is that really the same rattle you heard in the first place? I'd put strings back on and hold saddle down on edges while playing note hard and see if you still hear it. If you do, repeat on bridge, each of the tuners, nut, strap holder. Might have to have someone check braces after that.The source of a buzz can be anywhere on guitar, and for me sometimes hard to locate. Like said in prev post. Don't get it too tight. Long ago I made  my own saddle and thought it should be tight as possible. What started as tiny cracks eventually split bridge in 2.(took a LONG time)  The good part was that 15 years after getting guitar and explaining to Larrivee that I knew it was my fault, they still sent free replacement complete with inlay. (L-10) Like a 150.00  value.

Thanks for the replies.
  I have kept the room that is stays in humidified with a room humidifier and I also have a small case humidifier in the little holding compartment of the case as well as a planet waves humidifier in the strings, which I refill every other day. I live on the prairies of Canada so it gets real dry hear in the winter. I do have a  hygrometer in both the case and the room and they both read consistently between 40% and 45%. The temperature sometimes drops down to 16 C during the day but is always around 22 C when people are home.
  I am almost certain that the noise is coming from the saddle/bridge area. I was worried that it was the guitar itself but I am pretty sure it isn't. When the saddle is in it makes the same noise, strings or no strings, (although it is much louder with out strings). Now with out strings I can get the rattle to happen by only tapping the top. But with strings on I have to play the low E and A pretty hard to get the rattle to happen.
  When I take the saddle out and tap the top, nothing, just a solid sounding top.
  I remember reading that a saddle shouldn't be too tight or else the bridge will split. Maybe I made it too small and it has always rattled, but I don't remember hearing it before now.
  Has anyone else experienced trouble with a rattling saddle?
  I should say that maybe the word "rattle" is a bit misleading. It is not an in your face rattle, more of a hum or drone when the guitar is being strummed. I can hear it when I am playing but my girlfriend can't when she is listening (I have tested it out on her). So it isn't a real big deal if others can't hear it, but I can hear it.

The saddle may be a hair loose, but it's just not going to rattle when the strings are installed because there's 160 to 185 or so lbs. of tension holding it down.  No way.

In CAnada it's the middle of spring and the temperature and humidity is rising.  This is not the time I'd be expecting my bridge to shrink from dryness.  It should be swelling a bit, if anything.  If you're using both room and in case humidification it shouldn't be too dry.

When you remove your strings you're changing the load on the top and it's harder to locate rattles.  It really sounds more like a wolf tone than a rattle anyway.  Is it prominent on just one note?  A technician would be better equipped to deal with this, and they'll usually say you need to have it in your hands to really tell.

Funny thing, when I got back onto it a few years ago I thought I had a wolf tone on my low G.  What is was, I wasn't pressing close enough to the fret when I played an open G chord and it was buzzing.  But it sounded exactly like it was coming from the body.  It's just not always that easy to find these things.