Can the microphone be replaced/fixed?

I just recently bought a used Valve Index. Despite what I try I can’t seem to get the mic to work at all. I’ve listen to multiple online forums and videos and NOTHING has worked. I’ve made sure it wasn’t muted anywhere, this is including SteamVR and the control panel. Windows picks up the mic and displays it at the default but the mic just doesn’t work. Even plugging in my regular gaming headset to the Index, the mic from my gaming headset doesn’t get picked up but I can hear the sounds. Can the Valve Index mic be replaced or fixed? Where would I take it? Can I do it myself?