Warning: Do not use Cheap USB dongle.
There are lots of USB "soundcards" on the market, many Chinese.
Those are no good for this application. The Mic input is mono, it must be stereo.
Even worse, on those "cards" these a DC voltage on the mic input.
This can mess with the amplifier circuit.
Before using any sound card, allways check the capabilities of the device.
DO NOT set your input device for BOOST if it is avaliable.