I used to run Hackintosh and most tricky parts were
Sound card, WiFi module and GPU.
WiFi module and GPU are easily replaced but for Sound card, I always used USB DAC.
It is because Mac does not have an independent sound module like PCs. It is integrated in the Logic board.
So it seems natural to me that the easiest solution is USB DAC for your mac.
It's ordered, thank you.
Bisou
When you get your new USB audio adapter and plug it in, go to the Gnome Extensions website.
https://extensions.gnome.org/extension/906/sound-output-device-chooser/
If this is your first time on that site, it will have a notification up at the top of the page that is asking you to install the Gnome Browser integration, please click the install link to install it.
Then, at the link I provided above, you will then see a toggle button show up on the right side of the page.
Please click the toggle button to install the extension, a popup will come up asking you to confirm, by all means, do confirm it.
Now your extension is installed, and it can be found on the right side of your taskbar.
This is an awesome extension, it allows you to easily select which audio device you want to output too quickly. Your going to need it.
Hi again,
I have another problem. With my USB sound card, when I'm powering off my computer, I have a big noise buzz.
Here my sound card Ugreen External Sound Card
To stop this, I have to unplug the USB sound card. This is really not practical in my case.
Have you ever encountered this issue ? Do I need to buy another one ?
It seems you are not the only one complaining about humming noise:
https://www.amazon.fr/product-reviews/B08Y8CZB2S/ref=acr_dp_hist_1?ie=UTF8&filterByStar=one_star&reviewerType=all_reviews#reviews-filter-bar
Leider nicht zu gebrauchen, nach dem einstecken kommt sofort ein starker Netzbrumm
UGreen makes good cables but I do not how good their other products are.
Among the above photo I posted, I think Soundblaster is most trustworthy.
https://www.amazon.fr/gp/product/B073KTPNDR/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1
If you got it from Amazon, return is easy.
Thanks, I will try the Creative Sound Blaster.
I missed this one 
Yeah, I have already asked for a return and received the return instructions 
Vive la poste
It is Amazon's trick to place negative reviews in a less obvious place
I hope you will find SoundBlaster works better for your mac.
Funny, it says compatible with Windows 7 and 8. Nothing mentioned for Linux. But in reality, I've never seen an external DAC which is incompatible with Linux.
Whenever I shop for hardware for Linux, I try to put Linux in the search. The greatest compatibility, will always be those that state Linux is the title or description.
It depends. For USB DAC. I do no bother.
It is Windows which requires additional driver but not Linux. It is integrated in kernel.
Actually I found some claims for "Linux compatible" are not very trustworthy. I am sure UGreen is more reliable than other brand-less products. But the performance is another question which is what Salamafet experienced.
Luckily at French Amazon, there is a selection for return reason for "poor performance".
In America we can issue returns too. I just wish one of the reasons for return options was......
Return Due To Manufacturer Incompetence
Then I'd like a feedback option to go with it. How soon would you like manufacturer to become competent?
Immediately
Another coffee choking alert 
Before I buy their product!
Sound Blaster Adapter works like a charm. And in bonus, I have a better control on the high volume 
And yesterday I solved my slow startup problem. Everything is fine, and I can use Zorin OS without Mac OS bug 
.
Thanks again for your precious help.
vivre le Zorin 
Your welcome for the precious help. I already ate my precious, a big giant box of Chinese food. And I earned it after all the work I did today. Enjoy your new SB USB adapter. You see, sometimes, you just gotta think outside the box, and thats the way the cookie crumbles.
See my reply no. 16.
https://www.amazon.fr/Creative-Sound-Blaster-Play-USB-DAC-Amplificateur/dp/B073KTPNDR
Ah so you bought it for Salamafet. Kind of you to do that 
EDIT: for future reference, the Sound Blaster Adapter that works like a charm is: Sound Blaster PLAY! 3 - Sound Blaster - Creative Labs (United States)