I was having this issue, didn't gather much info on in, but I was on Ubuntu 18.x LTS, my Dell Vostro was detecting 3 mics, when I actually had only 1. I reinstalled Ubuntu, 20.04 now. At first glance it was detecting the same mics and some buzz noise, same with the 18.x, but then after the initial update, I restarted my pc and now it's all working, and it only detects 1 mic
I was having this issue, didn't gather much info on in, but I was on Ubuntu 18.x LTS, my Dell Vostro was detecting 3 mics, when I actually had only 1. I reinstalled Ubuntu, 20.04 now. At first glance it was detecting the same mics and some buzz noise, same with the 18.x, but then after the initial update, I restarted my pc and now it's all working, and it only detects 1 mic