These preferences let you set the audio output and input drivers, set the size of the I/O buffer, set the audio sample rate, and choose which note is displayed as middle C.
Note: Use of the I/O Safety Buffer preference increases the output latency and therefore the round trip (input plus output) latency.
The latency for the current buffer size is displayed below the I/O Safety Buffer checkbox.
Alert me: Displays an alert when a device is hot-plugged. The alert includes buttons allowing you to use or ignore the device.
Automatically Use Device: Switches the audio drivers to allow immediate use of the hot-plugged device for audio input and output.
Do Nothing: Does not switch the audio drivers.
The Silence Previous Patch preference applies only to audio and external instrument channel strips, not software instrument channel strips.