1/4'' ding / chip on a glossy black speaker

Try to find a local furniture repair woodworker. It will probably be very costly to be returned to as new condition if that's even possible, but they should be able to make it look much better for a more reasonable cost.

Before you do anything you'll need to find out what kind of paint is on the speaker and if it has a clear coat. Once you have that, try a body shop and/or a place that does powder coating.

Try black auto touchup paint (usually in the little glass vial with a small brush). I've used this to touch up a black electric guitar ding and it can work. Use multiple coats and wet sand with small grit followed by some car wax to fine finish it.