Do you want virus with that?
Two far eastern media players have been shipping with malicious code installed in the last two days[1,2]. Calls for the memory media player makers to test all their products with Anti Virus software miss the point slightly.
Anti Virus software will never be 100% effective. A small amount of prevention is worth more then a large amount of detection/removal. Take a real world example. Would you rather take a blood donation from a nun or from a drug addict prisoner whose donation is tested. In the prison case there is always diseases out there that no test exists for yet. By taking tested blood from a dubious source you are risking not hepatitis A,B or C (they can be tested for) but the rest of the undiscovered alphabet out there.
Adding virus detection to production of hardware is a good idea only if it does not lead to sloppy hygiene in the manufacturing process. An attitude of “well it is being tested anyway so we can do whatever we want” is easy to create.