High Latency or Failure to Open 24 bit Device in WDM
Last updated on 3/31/2016The information in this article applies to:
- SONAR 8.0.1 Producer Edition
- SONAR 8.0.1 Studio Edition
A new AUD.ini variable was introduced in SONAR 8.0.1 to address a problem where some devices exhibited a higher latency in the WDM/KS driver mode when running as a multichannel audio device. This actually works around a driver issue where using a WAVEFORMATEXTENSIBLE format to talk to the device results in the driver exhibiting a higher latency. Also, it's been found that some drivers rely on the older WAVEFORMATEX format and fail to open.
The new variable UseExtensibleForMultiChannelIO is defined in the per device configuration section in the AUD.ini file. When set to '1' (default), the driver is initialized with a WAVEFORMATEXTENSIBLE format when it exposes multichannel pins. This is the default behavior and is the Windows standard for multichannel I/O. If you experience problems with multichannel audio drivers in WDM mode, setting this value to '0' in AUD.ini for the device in question may help resolve it.
To change the variable:
- Close SONAR completely
- Open the Run Prompt, hold down the Windows key (located between CTRL and ALT) and then press R on your computer keyboard
- Type the following into the prompt: %appdata%\Cakewalk
- Navigate into your SONAR 8 Producer or Studio Edition folder
- Locate and open the file named AUD or AUD.ini by double-clicking on it
- Locate the section with your audio devices configuration information. It is the section that starts with [yourdevicename]. For example, if you had an Edirol UA-1000 it would appear: [EDIROL UA-1000 (6 in, 5 out)]
- Locate the line that reads: UseExtensibleForMultichannelIO=1
- Modify it to read: UseExtensibleForMultichannelIO=0
- Click File and then Save
Note: You must change this variable in AUD.ini BEFORE SONAR starts running, using the Edit Config File button from within SONAR will not allow the change to be overwritten.