// for device see "index" in "pacmd list-sources"
// (or full device name)
svoid linux_recordAudioOutput(File wavFile, S device, double duration) {
  backtick_verbose("parec -d " + pqO(device) + "|sox -t raw -r 44100 -e signed -c 2 -b 16 - " + pqO(wavFile) + " trim 0 " + formatDouble3(duration));
}