Greetings all, I recently bought a new desktop computer, iMac (Retina 5K, 27-inch, 2020), am running OS 12.3. When I went to use the headphone port for the first time, the audio continued to play through the computer's built-in speakers. I double checked that my jack was in properly, and that the correct setting for the headphone port was selected. I tried switching between settings but to no avail, finally started to poke around online, saw the tried and true suggestion of restarting the computer, which I tried, with success. HOWever, later today, I found that once the jack was removed, then reinserted, the problem was back. So I have come to this fine site for suggestions. 
Thanks in advance.
Thanks in advance.