In all other USB audio adapters (I have about 8 tested) catch, this distorting after a few seconds / minutes on the Mac and maim. Therefore you are glad to have finally found a reliable audio adapter.
Noise (even at full Lautsträrke): zero (Mac OSX Yosemite 10.10.2). Really no perceptible noise (and I am extremely sensitive to noise).
Only the Y-cable you should adopt and establish a properly stable because these thin lines may not hold in everyday life long.