Hi Bob and welcome to the forum.
Your audio hardware is different to the OP so I may suggest Mods split this thread.
We are seeing a lot of Intel sound issues of late. My websearches with search term: "Sunrise Point-LP HD Audio Ubuntu 24.04" (as Z18 is based on Ubuntu 24.04) also do not expose any clear solutions.
I assume you have tried playing with alsamixer as my suggestion here: No build in microphone HP laptop 17-cp2xxx - #2 by zabadabadoo
I assume your PC is quite recent. Can you tell us make and model? If it is recent you may need to install a more recent linux kernel, but let's wait and see if others here can offer more advice re your sound hardware and Z18.