Re: Default device frequency changes between calls.

On 01/08/2013 05:02 PM, Troy Watson wrote:
> I've noticed when using the default install of OpenAL Soft 1.4 on Kubuntu
> GNU/Linux 12.10 that the device frequency is sometimes 44100Hz and other
> times 48000Hz.

That would likely be PulseAudio's fault. Starting with version 2, it 
added the ability to change the playback frequency depending on what the 
app wants. By default OpenAL Soft specifies PA_STREAM_FIX_RATE, which 
basically tells Pulse "I don't care, just give me whatever's in use". 
When it does that while nothing's playing, it'll give back either 
44.1khz or 48khz for most people.

I find that behavior rather annoying personally, since it won't try to 
change the playback rate while playing. So if you have one app that 
requests a 44100hz stream and another that requests a 48000hz stream, 
the actual device output will depend on the order the two sounds are 
started in, and then stay that way until all streams stop. Plus the 
behavior of apps that don't strictly care will change depending on what 
was last set and how long ago it was set (I've noticed OpenAL Soft will 
get 44100hz for a while after Flash has played sound, and eventually get 
48000hz some time after Flash has stopped).
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