Well to make sure it isn't the chips I would do this.
With the two that hate you. Make sure that the wires Y & B are in the right place and tight. Then connect to PC. If nothing, heres what I would do next. Take a Y & B from a good chipset and use it on the two that hate you. Then plug them in USB and if it works, you know it is the wires. Contact your seller and tell him. He could just mail you the wires for like dollar or two in shipping.
If the chips still hate you, and they just might cuz QC sucks ass at most of these places. Tell him that you have tried everything, and it is his resposiblity to replace things that don't work. If he is in Canada, there are some nice laws on your side. As well as trade laws that are on your side. Which I'll let you look up if you ever feel the need to go to that.
In any case next time you might what to try out. modchip.com or one of there sister sites. There UK baised and I have't had a problem with them yet.