Teensy3.2 not responding on USB-serial when A2 and A3 used in Audio library

[nhk]

Edit:
Digging around in the Audio section of this forum, I found the answer, so I am adding this note: on what I think is the problem for anyone else running into the same issue ->
OK, the Audio library is not set up for A3 . So the second AudioInput statement for A3 puts the Teensy in an undefined state and even the setup does not execute..


------------------------------
Hi,

on Teensy3.2 -> I am attempting to use the Audio
mixer with two adc inputs, so I can mix adc1(A2) with ADC2(A3).
(eventually I need to use mixer gain with a negative gain on A3)

However, The moment I include the second audio input, the serial
stops responding. I have included (modified from example ) code below.

Q1: Can I use adc1(A2), adc2(A3) to feed into Mixer 0, 1, then
use gain of -0.50 on adc2 connecting into mixer 1
(Not in the code below -- but just asking)
Q2: Why does the serial on fail? Is my Teensy3.2 or is it
a "known" feature Or ??

Thanks
nhk

__________ Code ______________________

/*
Serial Event example

When new serial data arrives, this sketch adds it to a String.
When a newline is received, the loop prints the string and
clears it.

A good test for this is to try it with a GPS receiver
that sends out NMEA 0183 sentences.

Created 9 May 2011
by Tom Igoe

This example code is in the public domain.

http://www.arduino.cc/en/Tutorial/SerialEvent

*/
#include <Audio.h>

AudioInputAnalog adc1(A2);
AudioInputAnalog adc2(A3); // un-comment to turn on Serial on Teensy3.2

String inputString = ""; // a string to hold incoming data
boolean stringComplete = false; // whether the string is complete

void setup() {
// initialize serial:
Serial.begin(9600);
// reserve 200 bytes for the inputString:
inputString.reserve(200);
}

void loop() {
// print the string when a newline arrives:
if (stringComplete) {
Serial.println(inputString);
// clear the string:
inputString = "";
stringComplete = false;
}
}

/*
SerialEvent occurs whenever a new data comes in the
hardware serial RX. This routine is run between each
time loop() runs, so using delay inside loop can delay
response. Multiple bytes of data may be available.
*/
void serialEvent() {
while (Serial.available()) {
// get the new byte:
char inChar = (char)Serial.read();
// add it to the inputString:
inputString += inChar;
// if the incoming character is a newline, set a flag
// so the main loop can do something about it:
if (inChar == '\n') {
stringComplete = true;
}
}
}




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