As in this thread? Here's my recommendation for how to get a fantastic photo of an empeg with back-lit buttons.

Step 1: mount camera firmly on tripod and place empeg in suitable location.
Step 2: turn out all the lights (i.e., total darkness) and take picture(s) with just the empeg's display and button illumination. Tweak exposure until you're happy (i.e., no blown-out highlights).
Step 3: turn on the lights to help illuminate the case properly. Unplug the empeg. Tweak and photograph to make yourself happy, but whatever you do, don't move anything.
Step 4: combine in Photoshop.

There are many different ways of pulling off the combination. One way is simply "add" the pictures together. The black parts of the lights-out picture won't have any effect when you add them to the lights-on picture. For best results, you may want to reduce the levels of the lights-on picture for the on-screen area (i.e., Photoshop glare reduction for your screen) and maybe for the buttons as well.

Do that, and you'll have an absolutely fantastic final image. You can justify your horrific deceit against nature by observing that the human eye has a much wider exposure lattitude than any camera, and you're just trying to recreate what you can see, as well as you can actually see it.