I use a clear case that gos over the entire DS like armor. The best part is it also lets you put a picture inside.

From there i also store my DS, games, charger, accesories, and whtnot in an official Nintendo carrying bag, which has been lovingly nicknamed my "Man Bag".

Ive owned 4 different nintendo DS's, two standard, and 2 Lite. Every DS ive had at some time or another exhibited this kind of odd behaviour, where at start up, the typical DS start noise, which is supposed to come out as stereo sound is played the same from both speakers.

The result sounds higher pitched and off key. It wont affect anything else, and its nothing more than a random occurence that every DS can have.

I imagine it's nothing more then a bug in the DS firmware, perhapse the code to play the noise loads before the ds audio drivers (Though i have no clue about the DS firmware and how it works).

Hope that helps 

DS Lite has a battery that lasts twice as long, and takes half the time to charge. The DS Lite screens can go up to 4X brighter and colors look outstanding.

The DS Lite Mic. is placed in a much more ergonomic posistion, as is the stylus. The Stylus itself is also much larger, only about a few centimeters away from a full sized Palm Pilot Stylus.

The DS Light is of course sleeker, weighs less, and is smaller.

The DS Phat is indestructible. it may end up scared and ugly as a leper, but it will certainly work. The DS Phat also comes standerd with a very nice thumb stylus, which i had to buy extra for my Lite (Makes plaiying metroid MUCH better).

DS Phat has more ergonimicly placed start and pause buttons, and the D-Pad is excellent.

In the end, DS is DS, and it's ALL about the games :D