This product is either discontinued or we cannot get that from suppliers.
Asus Compact Usb Sound Card Xonar U3, 100dB, THD+N <0.005 %( dB), Power 2Vrms, Audio Processor ASUS UA100, I/O 1 x 3.5 mm jack (1/8") (Analog out), 1 x 3.5 mm jack (1/8") (Line-in/ Mic-in combo), 1 x S/PDIF out (1 x Optical (Toslink)/(combo with analog in).
Get a BIG UPGRADE from USB audio with Xonar U3’s crisp and clear sound for music, movie, gaming and VOIP enjoyment.