Originally Posted by jazzman7
Your point is well taken. I am testing a specific setup, and another piece in the chain might fix things.
Right now, it seems that iOS 7 on the iPhone does not allow native 96k playback on the microStreamer DAC. Lower sampling rates are fine.
For the iPad, I did not update to iOS 7 yet. My thinking is that the iPhone 5c is faster than the iPad mini, so it isn't a processor speed issue. But as you say, it might still be a processor load issue, or something else entirely (e.g. memory bus). The iPhone and iPad are different.
I don't want to update my iPad until I know 96k works on it in the new OS. Unfortunately, I don't think I can easily test this in the store.
Regarding the Dragonfly, does it downsample 96k playback to lower sampling rates in your iPhone testing?
I'm glad my point was well taken - I sometimes worry about the fine line between "to the point" and agressive
I would perhaps try closing all the background apps on the 5c (which you can do 3 at a time with iOS 7's new app switcher!) and see if that makes a difference. Multitasking works differently on iOS 7 compared to 6 - you can enable/disable backgroud refresh on a per-app basis, for example. I guess the app used to play the music will make a difference too. I'm using iTunes Home Sharing with the stock music app but that's not to say other apps capable of 24/96 will work properly - which app are you using?
As for the Dragonfly, everything up to and including 24/96 is passed to the Dragonfly at the source's native sampling rate, as confirmed by the colour of the logo on the DAC. It switches flawlessly between 44.1, 48, 88.2 and 96 depending on the source. The Dragonfly is only capable of receiving up to 24bit/96kHz; 176.4 and 192 are downsampled to 96 before they are passed to the Dragonfly. I believe that iTunes on the host machine is doing this downsampling on the fly, based on previous tests I've carried out that demonstrate that, when using Home Sharing, iTunes will tailor the bitrate and sampling rate of what is passed to the client device based on that device's capabilities (which, when the Dragonfly is connected will be up to and including 24/96).
I have an iPad 3 that I've not yet updated to iOS 7 (just haven't had the time yet, plus my wife likes to play Minesweeper on it ) but I intend to. I will post about how that goes.