Asus S46CM boot issues

[Eduard]

Hello everyone.
I have an Asus S46CM laptop with Windows 8.
Recently I have disabled the Secure Boot BIOS option to use Ubuntu. It has come to my attention that when I attempt to boot my laptop with a USB peripheral [other than my external HDD with Ubuntu installed], my laptop is stuck at the boot screen until the "offending" device is ejected.
Is there a fix for this issue?

 

[DMGrier]

So does it ever go into the Ubuntu? I would also assume you also set external device "enabled" in the bios.

 

[Eduard]

Yes, it does. The problem is not with the external hard disk, it's more like if my laptop has a thumbdrive [with no OS] plugged in, and I boot my laptop, it freezes at the boot screen.