MacOS Mojave: Built-in vs System output

[Xekomi]

Hey @support , just had a bit of a problem with build 363, possibly due to resampling, on a device running 10.14.1 (18B75). For whatever reason, when configured as system output, playing back a 16/48 FLAC to built-in output resulted in loud static (or crashed the audio device driver), and switching back and forth between files with different sampling rates and bit depth would give similar weirdness.

Easily fixed by reconfiguring the device to built-in output of course, but still a bit weird, so figured you might want to hear about it.

[dylan (Dylan Caudill)]

Hi @Xekomi,

Can you share the signal path when playing to System Output?

Built-In Output allows you to use Exclusive mode and plays to the audio device directly while System Output plays to the OS Mixer. You can read a bit more about that here:

Difference between Built-in output and system output?[Answered]

To expand on the answer above a little bit: System Output is going to make Roon’s output function like any other application – audio is sent to the OSX mixer, where it’s mixed with other sources (Youtube, system sounds, etc). In many cases, the audio will be resampled during this process, so this mode is more about convenience than critical listening. For example, if you switch your default output from the Macbook’s speakers to a bluetooth device, Roon’s output will go with it, because it’s si…

[Xekomi]

Here’s the signal path.

Exclusive mode isn’t on (I’ll do that now to see what happens), and things aren’t really reproductible, it’s somewhat random (but Roon does keep on briefly loosing the zone when going from tracks with one sample rate to another). No biggie, just unexpected.