Run your forefinger around the grill and you'll feel a rounded out portion. Grab that between your thumb and forefinger and use that to pop the grill off.

If that doesn't work, just use your thumb and forefinger and work your way around the grill slowly and pull outward until it pops out.

Cheers,

Surround Music Fan/Computer Geek/Curmudgeon in training.
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