You have my full sympathy. I have a Kef Subwoofer that was perfect for 15 years. Looked like a Donald Judd artwork and then my 2 year old daughter put a ding in it. If you are obsessive-compulsive, like me, it will bug you to fix it and I second the mental aerobics of assuring yourself you will, one day, re-coat it professionally and then you'll probably find yourself just living with it. Having said that, if you really want to fix it yourself, contact Monitor Audio for advice. You need to identify what polymer or lacquer it is before investigating how to fill and polish it. There is always the chance you make it worse and a bigger eyesore than it currently is. You also need to be prepared to do the whole side or the whole speaker (looks like the edges are rounded) to integrate the repaired and polished section with the rest of it. I obviously don't have an immediate answer for you, but the manufacturer should be able to advise of the type of material that is coating the speaker, at the very least. Note: Different polishing compounds are designed for different surfaces - get that part wrong and you'll create some serious damage.