Because of the patch that removed the "user sources list" in libobs
(70fec7ae8), obs_enum_sources will now enumerate the global audio
sources, where it didn't before. In the advanced audio properties
dialog, before the patch I had to use code to manually include them, but
I neglected to remove that code when I made that patch, so it would
cause them to be added more than once. This just removes that code.
This fixes the issue where the labels wouldn't have enough space for
localization text in certain circumstances, and also fixes some issues
with alignment
In the advanced audio properties, the last set of controls designate
what tracks the audio of a specific source is applied to, but for some
reason I named it 'Media Channels'. It feels a bit confusing of a name.
I feel like it should really just be called 'Tracks' here for lack of a
better term.
This dialog gives options such as increasing audio past 100%, forcing
the audio of a source to mono, and setting the audio sync offset of a
source (which was an oft-requested feature)