There are various options you can try to achieve to complete the second way (2).
Placing the mints in a little bag - instead of carrying them around in a metal container, where they're bound to rattle, you could instead carry them in a little pouch type bag.
( Albeit un-stylish, it removes the rattling ).
Something like below is what I imagined would suit
You could place a piece of cloth/fabric inside - placed inside the container, into the empty space, essentially "filling" the container so much so that the mints don't rattle.
Padding the container with foam/cloth - albeit an extreme option, instead of filling the empty space with cloth, you could pad the container on the inside (If it annoyed you to the point of killing someone).
Basically, padding the whole inside of the container as marked in this image below.
What you want to do is pad anywhere the mints have contact to the inside of the container.
Essentially making a nice snug fit and "noise proofing" it.
As for your first issue, is the glove compartment empty?
Which causes it to easily rattle?
Or have you got other stuff inside there and the mints container is on top of that?
lifehacks.stackexchange.com/users/4019/Darren
to prevent the box from rattling, you could 'stabilize' the box by using adhesive velcro on the back of the box and its assigned spot in the glove box.
as far as rattling inside you could try: a "food safe" sealant or coating. try copy-flex liquid mold making silicone.
http://www.makeyourownmolds.com/copy-flex adhesive felt sheets like the ones used to line jewelry boxes - found at any craft store or use food safe epoxy to attach your choice of foam.
check out thefoamfactory.com you could line it in leather or any choice of fabric (wool, cotton, synthetic) too.
the trick is finding a food safe adhesive.
lifehacks.stackexchange.com/users/4152/david
Pad the inside of the box with a layer of cotton balls.
Pill bottles used to come like this, although I haven't seen it as much recently.
lifehacks.stackexchange.com/users/4666/Bowen
Try placing the container on its a side.
That way the mints will stack on top of each other in a smaller space and not rattle.
Neither will they be bouncing on a flat sounding board.
lifehacks.stackexchange.com/users/1961/subjectivist
You can try to do what Darren did with one variation: Put it in a sock.
The sock is pretty soft and should effectively muffle the banging sound.
The sound is created since the container and mints have a large space to bounce and bang into.
If you limit the space the mint box has to bounce and bang in, there will be little or no sound.
You can effectively do this by: Putting it in your cup holder Putting it in a bag filled with stuff like clothes or lots of paperwork You pants' pocket A small side pocket in any type of bag similar to this one: A backpack or luggage bag
This should significantly lower or eliminate the sound from the metal box and mints.
I hope this helps you!
lifehacks.stackexchange.com/users/2475/Anthony Pham
For preventing the box from rattling against the glove compartment, what about keeping it in a seat pocket or on top of your visor instead?
lifehacks.stackexchange.com/users/1876/Random832
I like to keep fresh breath mints in my car. They come in a box like this:

The problem is they rattle in two ways:

The box is metallic and it rattles against the glove compartment (or other compartment) of the car
Inside the box, the mints start to rattle once the box is less than 1/2 full.
Short of always filling the box and wrapping it in a sock, what are some ways to prevent the rattling?
Prevent mints from rattling in the car
lifehacks.stackexchange.com
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lifehacks.stackexchange.com/questions/5599
lifehacks.stackexchange.com/users/2201/Dan Dascalescu
There are a few ways that you can prevent mints from rattling the car. A simple way would be to pad the container with cloth or cotton balls. Similarly, you could keep your mints in a little bag instead of a metal container. You could also keep the container in a sock to reduce the rattling sound. Options are to put the mints in a bag, pad the container with foam or cloth, stabilise the box using velcro, put cotton balls into the box, place the box on its side, put a sock in it or put it in a seat box.
Try putting the mints in a bag, pad the container with foam or cloth, stabilise the box using velcro, put cotton balls into the box, place the box on its side, put a sock in it or put it in a seat box. Try stabilising with adhesive velcro. Pad with cotton balls. Place the container on its side. Put a sock in it. Try putting the box in the glove compartment or a seat pocket.