Just use the CD drive on your computer. I think what you are comparing to is dubbing a cassette and what you want to do is copy the digital coding on the CD directly to convert it in the computer. What you copy in this case is not reliant on the D/A converter of the Onix, it is merely the transferral of the information andthere is no need for an intermediary.
The only factor that will matter is if error occur during the process that are mainly a PHYSICAL problem i.e. defects such as scratches, unclean read surface or prior errors in creation of the disc as well as physical deterioration of the CD itself. Barring those the vast majority of rips will be fairly routine and flawless.
The biggest problem lies in creating a CD, based on mostly the quality of the media (burning speed mainly). Many, if not most modern burner programs can adjust for this to some degree of you can set it by trial and error. With the cheaper, read lower quality blanks generally available today (you can SEE THROUGH some) the speed used can be vastly curtailed vs. others.
Now, didn't you ask about extracting DVD audio?
Try this search query:
https://www.google.com/search?q=ripping+DVD+audio
Right off the top, VLC Media Player might do and there are a number of programs listed for such a task. I have VLC, perhaps I should update it all I can and try.