USB Device Not Recognized Plantronics DA40

Mac OS X; Leopard 10.6.8; Audacity 2.0.0

This is an old subject but I was hoping there would be new solutions. I have just purchased a Plantronics DA40 headset with USB cable.

It has excellent noise cancelling and a great mic. I can set input to this headset in Audacity and Audacity has no problem recording from it. But if I set the output to this device, and try to play back i get this message.

“Error while open sound device. Please check the output device settings and the project sample rate.”

I am listening to a recording with stereo, left and right tracks, 48000Hz. In Audacity, the headset does indeed appear, but the only option for channels is “Mono”

Is there any way to fix this?

The default sound standard is 44100 Music CD standard, not 48000 TV sound, but it should not make any difference. This may be a good time to Go > Utilities > Audio MIDI Setup and see if anything in there helps. The only other place to set things is Apple > System Preferences > Hardware > Sound > Output, but you can’t change anything in there.

If the headset announces itself as mono to the USB system, there isn’t a lot you can do.

The headset may have two muffs, but where does it say that it’s a stereo headphone? The web sites claim this technology is an offshoot of the telephone system and the telephone system is mono.