You should look at the AudioInjector web site (www.audioinjector.net
, for the "Octo Soundcard". Support has been a bit scanty of late but their forum has been pretty helpful. I have the basic stereo card and I am currently having problems getting it to work from Raspbian Stretch...it previously worked well from Jessie and I should have left well enough alone but... Previously, the Stereo card worked fantastically for ripping old vinyls to .wav files.
On their web forum, "flatmax" has indicated that there may be a problem with the current RPi kernel and recommends going back to an earlier edition. I am not sure if this is my problem with it and will investigate further. "flatmax" (forum moderator) has apparently been MIA from the forum for about 6 months but is back now with a Jan. 7. 2019 post and a new Amazon Store page has sprouted as well, with a much pricier Ultra 2 card for sale.