Today I BARTed back to work and put the iDSD through its paces with the iPad, iPhone, and my Mac Pro desktop at the office.
Some observations:
* The iFi nano iDSD + Apple Camera Kit doesn’t work with the iPod Classic 160gb. Or, at least, it doesn’t work with mine. I assume it’s optimized to work with iOS7 and not Apple’s hard-drive-based mobile devices, like non-flash iPods.
* The iDSD doesn’t work with my iPhone 4S + Camera Kit no matter how well-charged both devices are. I don’t even get the “device is drawing too much power” message anymore. The iFi box simply delivers no output.
* I plugged the iDSD into my MacPro 2010 model running 10.8.5 and played FLACs in Decibel and Cog. It worked fine at first, then went intermittent on me, then the output stopped altogether. I rebooted everything and it still wouldn’t work. I worried the iDSD had failed, and plugged it into the iPad. Presto! It worked. I plugged it back into the MacPro and everything seemed OK again.
When the box was working with the Mac Pro, it sounded wonderful through the AKG K240 headphones I keep at the office. Except…one not-so-minor quibble: the volume through headphone amp portion of the device wasn’t adequate. It was barely higher than the highest “safe” volume on the iPad, even when everything was cranked up to the maximum. Lots of fiddling and attempted gain-scaling didn’t solve the problem.
* On the way home I used the Camera Kit to plug the iDSD back into the iPad (photo right). The train was 
crowded and there was jostling. I was juggling the iPad, the iDSD, my headphones and a backpack between my knees. The Camera Kit plastic dongle thingie would come dislodged from the iPad port. Reaching down to turn up (or down) the volume on the side of the iDSD was awkward. I’m not sure this thing was made for short commutes.
I wrote a brief, polite email to iFi’s support address letting them know about the iPhone issue and the problems I had with consistent output on my main desktop machine at work. We’ll see what they come up with; I’m not feeling especially enthusiastic about my $189 purchase at this point. Stay tuned.
