3 ms·
At which point the system will helpfully switch to the built-in mic.
At which point the system will helpfully switch to the built-in mic.
As it might/probably will happen by turning off the USB port.
I can disable the on-board sound card in the BIOS settings on my Thinkpad (T440p),
so unplugging the USB headset should do the trick (but then there's no music either).