Saddles

Next time you change your strings, take them all off at once.  Don't worry, the neck won't warp as long as you restring the thing right away.  That bit about never removing all the strings at once is an old wive's tale.  I wouldn't leave it that way for a week, but you can do it while you clean, adjust, and restring.

As you loosen the strings prior to pulling them, carefully make sure your nut is glued in place, and if you should do this on a guitar with a floating bridge, make SURE you've marked the bridge position so you can put it exactly back in place.

But I'm assuming you've got a normal acoustic.  If that's the case, use the opportunity of having all the strings off to clean your guitar and wipe the fretboard and bridge down with lemon oil (available at music stores) and a soft cloth.

While it's unstrung, check the fit of the saddle in its slot.  It should be snug and fit in the slot squarely.  Not tight, just snug, but easily removable.  It should not be loose.  A loose saddle, which is very common on less than heart-attack expensive guitars, will have a bad effect on sound and could even damage your bridge.

If your saddle is able to slop around in its slot, shim it.  Look carefully at how it sits in the slot before you remove it, so you can put it back exactly like it was.  You don't want to swap ends when you replace it.  It needs to go back in just like it came out.

You could use tiny strips of paper or very thin wood, or even tape to shim the saddle if it needs it.  Just make sure you seat it squarely and snugly in the slot.  Do a neat job and don't shim the underside unless you want to raise the action.  When I get a new guitar, if the saddle is loose, I use very thin, white Teflon plumber's tape, the kind they usually use on pipe threads, to wrap around the saddle lengthwise until it snugs up.  I trim the excess tape hanging past the bottom edge of the saddle before I install it in the slot.  This seems to work very well and to transmit sound very well.  But if you use Teflon plumber's tape, you do so at your own risk.

I haven't had any trouble, but there are some things that will react in a very negative way with your guitar's wood or finish (vinyl on a lacquer finish comes to mind - don't buy vinyl straps or leave your guitar on a vinyl couch or car seat).

Anyway, snug that saddle up then restring.  You might be surprised how much better your guitar sounds if the saddle was a sloppy fit.

Oubaas