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roughly the 1st second of every track is fading in
#11
The USB specification states that whenever a device is not in real use (like when stopped playback), the device must be set in what's called 'alt setting 0', which does not reserve/consume any USB bandwidth. This frees up USB bandwidth to be used by other devices. This is what we have always been doing. Although not really relevant on Android or this app since it's unlikely that you'll use other USB devices, but we'd like to play by the rules nevertheless. Furthermore, it may consume less power. On desktops, you'll see that it often does not switch to 'alt setting 0' though, perhaps only when the PC goes into 'sleep' mode.
When the device has been switched from 'alt setting 0' to another 'alt setting', the Chord devices fade in audio, probably to defeat issues with DoP (DSD-over-PCM) signal detection.
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#12
(07-01-2016, 11:11 AM)dwrae Wrote: The USB specification states that whenever a device is not in real use (like when stopped playback), the device must be set in what's called 'alt setting 0', which does not reserve/consume any USB bandwidth. This frees up USB bandwidth to be used by other devices. This is what we have always been doing. Although not really relevant on Android or this app since it's unlikely that you'll use other USB devices, but we'd like to play by the rules nevertheless. Furthermore, it may consume less power. On desktops, you'll see that it often does not switch to 'alt setting 0' though, perhaps only when the PC goes into 'sleep' mode.
When the device has been switched from 'alt setting 0' to another 'alt setting', the Chord devices fade in audio, probably to defeat issues with DoP (DSD-over-PCM) signal detection.

Thanks again for the clarification!
A VIP member from Head-Fi pointed this out to us, directly from the man himself (Rob W.):

"The problem of muting the initial start is due to certain OS and apps - when the sample rate changes, the data in the buffers get sent out at the wrong rate. When you switch from DSD to PCM you then get a loud bang, or track played at the wrong rate for a period. Now this fault is in the app, its absolutely nothing to do with the DAC.

So to fix the apps problem, if the sample rate changes, I force a mute for 0.5 seconds, so that you do not hear these noises. On some apps, you can force a small silent period at the beginning and this solves the issue.
If I didn't do this I would have people complaining about bangs thumps and music being played at the wrong rate. Better silence than shots being fired off!"
Traveller - Genève * Melbourne * Miami * Wien

LG G4 + UAPP > Chord Mojo / AQ DragonFlyRed (+Jitterbug) >
A&K-JHA Angie II / Etymotics ER-4S / Grado SSR-60/225
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#13
Sure, but funny enough there are 100+ DACs that do not suffer from this problem.
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