Turn off timer on AudioOut deinit.
Turn off timer on AudioOut deinit.

Thanks to @sommersoft for spotting the error.

Fixes #850

adafruit/circuitpython,adafruit/micropython,adafruit/micropython,adafruit/circuitpython,adafruit/micropython,adafruit/circuitpython,adafruit/circuitpython,adafruit/circuitpython,adafruit/micropython,adafruit/micropython,adafruit/circuitpython