If you're going to sell something on eBay you need to be prepared to do a few things: 1) add plenty of high quality, well-lit photos showing the item (and any flaws), and all included accessories clearly from all angles, 2) write a decent description mentioning any faults or flaws, as well as highlighting how otherwise excellent the item is, to encourage bidders, and 3) take photos of the packaged item, including the shipping label, before it goes out the door. These steps should defend you against any fraudulent SNAD (significantly not as described) claims. Yes, eBay's automatic systems tend to side with the buyer in most cases, but if you stick to your guns and raise it with their support team then the innocent party usually will come out on top.
Do not use terms like "as new", "like new", "like brand new", or anything that could imply the item is completely 100 per cent blemish-free, unless it is literally a brand-new, unopened product.
I have sold a lot of electronics and hifi gear on eBay over the years, both cheap and expensive, and have luckily not had any issues yet. Only a couple of issues where the buyer for some reason has refused to pay. This is annoying mostly because I wait for the fee promotion weekends to list stuff, and if you need to re-list something, you have to wait until the next promo!
I have also bought a lot, and have had my fair share of items arrive not as described. I never go straight for the jugular of raising an eBay dispute though - I message the seller directly first in order to work out an amicable solution (i.e. a return, or partial refund).
I've also had some bargains thanks to taking a punt on lazy listings with a couple of crappy photos and/or whose auctions end in the middle of the day on a week-day