PC does not see USB device but sees others

[OvenMaster]

Device to be connected:
Behringer U-Control UCA202 USB audio interface with digital output
http://www.behringer.com/EN/Products/UCA202.aspx

Machine 1
Emachines W3118
AMD Sempron 3100+ 1.8GHz
768MB PC3200 RAM
WD 80GB WCD800BB hard drive
Nvidia GeForce 6100 onboard graphics
Realtek onboard sound
Windows XP Home SP2 (fresh install from restore disc after "Missing Operating System" boot error message)

Machine 2
Toshiba L305-S5944 Laptop
Intel Pentium T3400 mobile processor dual-core 2.16GHz
2GB PC6400 RAM
250GB SATA hard drive
Mobile Intel 4500M graphics
Intel onboard sound
Windows Vista Home SP2

Machine 3
Asrock 880GM-LE motherboard
AMD Athlon II x4 640 3.0GHz
4GB Kingston DDR3 1300 RAM
WD 160GB WD1600AAJS SATA II hard drive
AMD onboard HD4250 graphics
Diamond Xtreme 5.1 PCI soundcard
Windows XP Home SP3 and Windows 7 pro 32-bit

Here's the situation.
When connecting the Behringer USB audio interface to Machine 1, it is not seen or recognized by Windows. There is no prompt in the systray and it does not show up as a USB codec in Device Manager as it should. The power indicator on the interface lights up.

When connecting any other USB device to Machine 1, (thumb drives, digital cameras, keyboards, mice, etc.) it is immediately recognized by Windows, the driver software is installed automatically, and it's ready for use.

When connecting the Behringer USB audio interface device to Machine 2 or 3, it is recognized immediately by Windows, the driver is installed automatically, and the device is ready for use.

So... what's stopping Machine 1 from seeing the USB sound device? Any ideas?

 

[S.T.A.R.S.]

Have you tryed other USB entrances on Machine 1 to see if it works?

 

[OvenMaster]

Yes. And the problem was solved last night.

It turns out that the Behringer USB device does not pop up a balloon notification, nor does it announce new hardware in the systray like every other USB device does. It just automatically changes stuff in Sound Properties in Control Panel, showing up as "USB Codec", which we found out by accident.

The device works just fine when connected to my friend's Akai Miniak keyboard.