Don't ever close a case at the seller's request (you can't open another with eBay) this is a known ruse to time out the 30-day eBay MoneyBackGuaranty. once past 30 days of delivery you can only open a PayPal dispute but then you would be required to return the defective tablet to China at your own expense including online viewable tracking - which can cost as much as you paid for the tablet.
Ask for refund only and nothing else, eBay will require the seller to either send you the money or a prepaid label. Since they are in China they cannot send a label, get the money for return upfront or ask eBay to step in - if they still refuse eBay may refund without you having to return the item.
Before accepting any money make sure it will be enough to cover the cost of return shipping, you will be surprised at how much it will cost with the required online tracking needed. Once the money is accepted you will only have 5 days to get an acceptance scan at your post office or the seller will win by default.
BTW, tablets from China will always be of low grade, I got taken twice over the years and now only by a name brand from office depot.
ps. if you both agree to a partial refund that may be the easiest way to handle this, but only if you think the item may be worth keeping at the reduced price.
