Thanks for the tips everyone. I've engaged the folks at Burson while investigating this problem. Here is what I wrote in my latest email:
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I really appreciate you taking the time to help me with this.
I have made the settings on my iMac as close to those shown in the screen shots [you provided,] and the behavior is still the same. I tested on a MacBook Air, also running OS X 10.7.2, and experienced the same results. The screen shots that you sent are from an earlier version of OS X. Are you aware of anyone using a HA-160d on OS X v.10.7.2?
I found a valuable clue when I checked the kernel.log after trying to play a 88.2 kHz song from iTunes after making these Audio MIDI Setup changes, and found the following line repeated several times:
Jan 18 23:21:37 myimac kernel[0]: USBF:426104. 33There is not enough USB isochronous bandwidth to allow the device "Burson Audio USB DAC " at location 0xfa130000 to function in its current configuration (requested 582 bytes for endpoint 0x3 )
The HA-160d is on it's very own USB bus. A single cable runs from the rear of the Burson to one of the [precious few] USB ports on my iMac. It was also the only device on the chain when testing with the MacBook Air. In fact, it was the only USB device connected to the laptop at all.
I Googled "osx There is not enough USB isochronous bandwidth to allow the device" and saw a few results from others with similar problems using competing DACs. I'll confess, I wasn't using the nifty blue USB cable that was supplied in the box with my Burson, as it wasn't quite long enough to reach where I really wanted to set the amp on my desk. I did manage to find it in my basement just now and I tested again for thoroughness.
Same error.
I tried a different USB port on the back of my iMac- same error again.
I'm a computer sysadmin by trade, so I'm familiar with basic troubleshooting. I think I covered most of the bases here (different cables, different ports, different computer).
Any suggestions? Thanks again.
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Is anyone here using a 96/24 DAC on OS X Lion (10.7) successfully?
Jaywalk3r- Do you mean an optical connection from the headphone port? Unfortunately, my Burson only supports USB and coaxial.
Roseval- I haven't messed with Apple's USB developer tools, I'm only going by the tech specs on the Burson web site. It still says that the DAC supports 24/96 input.
I'll pass along anything from Burson as I receive it.
Thanks again all!