[aaronem]

No, clear is a requirement so that the guards can see it's not stuffed with marijuana or heroin or something.

[sanoli]

This. They do the same with typewirters:

http://www.swintec.com/8-clear-typewriters

[aaronem]

Anything else with sufficient internal voids to conceal contraband, too, I should think. It's a lot easier than taking every such item to pieces during every inspection.

[nanidin]

These are also examples of tampering with the radio, just more obvious (to me at least) than modifications to the actual functionality of the device.