I recently installed Zorin OS (Pro version) on my laptop. The audio works fine when I am using the internal audio output of the laptop. However, the sound randomly skips when I connect an external audio output device.
The audio device is a Logitech stereo speaker which is connected to my external monitor which is then connected to my laptop using an HDMI cable.
Previously I had a dual boot setup between Windows and Zorin OS and never faced such a problem. I recently removed both OS and did a clean installation of only Zorin and started facing this problem.
Sound problems where a HDMI cable is involved is reported here quite regularly. Initially you should try a different HDMI cable or even reversing a HDMI cable, as some are directional.
Does the same problem occur when you do a "Try Zorin" from the Zorin installation USB?
As you have just had a fresh Install, can i also suggest, with the external monitor connected & turned on,
Then Open "Software Updater" , click "settings" & then open the "Additional Drivers" TAB & see if you have any further drivers that may suit you, if needed select the driver & follow the prompts, Then run the main update.
sudo apt update && sudo apt upgrade
Try again, if this doesn't help please show us the output of these:
sudo lshw -C display
sudo lshw -C multimedia
Can you also tell us which Edition of Zorin OS your using, Pro Core or Pro Lite.?
Hope this helps.