This is precisely what happened to me. I couldn't figure it out myself, but I made use of it anyways. Might be in for more when it gets to RSA customs. Will update if that's the case.
I do know that if it is declared under 8528.49 in the SARS excise book "85.28 Monitors and projectors, not incorporating television reception apparatus; reception apparatus for television, whether or not incorporating radio-broadcast receivers or sound or video recording or reproducing apparatus:" it will attract a 25% import duty. Steep.
If it's declared under 9504.50 "9504.50 - Video games consoles and machines (excluding those of subheading 9504.30):" then there is no import duty, you just have to pay the 15% VAT (and can claim it back) on SARS valuation of the item (which is cost of item + shipping + 10%).
I'll try to keep this updated for those that care to know.