Reference Guide

1118
Improving audio performance
Improving performance with digital audio
ASIO drivers
SONAR supports ASIO drivers. You are limited to a single sound card when using an ASIO driver.
To use an ASIO driver
Use the following procedure to enable SONAR for use with an ASIO driver.
1. Go to Edit > Preferences > Audio - Playback and Recording.
2. Click the Driver Mode list and select ASIO.
SONAR re-profiles your audio hardware.
ASIO sample position
UseHardwareSamplePosition=<0, 1>, default = 0
This variable applies to ASIO mode only and controls whether SONAR internally compute the
sample position based on buffer switch calls or uses the ASIOGetSamplePosition reported value to
retrieve the driver reported value.
Some drivers change the reported sample position based on how long a buffer switch took to
complete and this can cause problems since SONAR expects the reported position to be in sync
with the number of buffers actually streamed.
This Aud.ini variable defaults to 0.
Minimize driver state changes
SONAR has an option to not reset audio devices each time playback or recording starts. This option
minimizes device state transitions in response to transport operations. When enabled, SONAR
attempts to keep the device in a running state as far as possible.
To configure the MinimizeDriverStateChanges option
1. Go to Edit > Preferences > Audio - Configuration File.
2. Under Configuration Settings, click Edit Config File.
The Aud.ini file opens in the default Windows text editor.
3. In Aud.ini, locate the entry called MinimizeDriverStateChanges and set it to the desired
value. For example:
MinimizeDriverStateChanges=1
Valid values are as follows:
• 0 = off.
• 1 = On for ASIO only (default).
• 2 = On for WDM only.
• 3 = On for both ASIO and WDM.