Asrock z75 pro3 cannot boot with usb drives attached

[btvbill]

If I have any USB drives plugged in my Asrock Z75 Pro3 will not boot up. It gets past the initial "welcome" screen but then I just get a flashing cursor. I have to then disconnect any USB drives before the PC will boot up. I have the boot order set in the bios for the CD then the hard drive. Any help would be appreciated. It's a pain to have to unplug all my usb drives and then have to plug them in again after starting the PC each time.

[ASRock TSD - Emily]

Dear btvbill,

We didn't see the symptom at our side.

Please kindly provide the detail model name of USB devices for us, we will check it again.

Thanks for your help!

Have a nice day
ASRock TSD
Emily