As noted in reply to @Ponce-De-Leon I did the highest version of 6.12 but got an error message and still no sound card. Thinking perhaps to try the highest number from main line which is 6.18 so as to overwrite the error and perhaps get sound function.
Is there a downside?
I have to go out but will resume in a couple of hours.
This sound thing is my last real problem before I can use Zorin for most things.
There is aemaining irritation about having to put in key ring and authentication passwords each time but that’s minor and I’ll worry about it after I get sound.