Antec Case USB ports

[Sparky Joe]

I have a new Antec case with a new ASUS motherboard. The case has audio, USB and firewire on the front panel. The motherboard has 2 USB headers, one says USB56, the ohter USB78. I've tried the case connector on both of them, one didn't work, the other only worked halfway(power, no signal). I also tried the back panel add on USB's that came with the motherboard, this worked on both headers. I read my case manual and it said I may need a USB adapter, has anyone heard of one of these? The diagram in both the manuals match up as far as the configuration. Any help would be appreciated.

Thanks -Joe