[LAU] reducing xruns (System configuration)

[david]

On 07/19/2018 11:24 PM, David Kastrup wrote:
> Ralf Mardorf <ralf.mardorf at alice-dsl.net> writes:
> 
>> On Thu, 2018-07-19 at 22:44 +0200, David Kastrup wrote:
>>> You are babbling. [snip]
>>>
>>> A lot of people get setups like that to work without rtirq .
>>
>> Hi,
>>
>> the OP on Wed, 2018-07-18 at 21:28 +0200 wrote "64 buffer size at 48kHz
>> 2 Periods/Buffer" and the OP on Thu, 2018-07-19 at 14:32 +0200 wrote
>> "Bus 003 Device 002: ID 08bb:29c2 Texas Instruments PCM2902C Audio CODEC".
>>
>> I'm not aware that a lot of people got this to work at all.
> 
> I missed the PCM2902C bit.  That chip is described in
> http://www.ti.com/product/PCM2902C/technicaldocuments and is USB full
> speed (namely USB1.1 speeds).  It is described as
> 
>      – USB Adaptive Mode for Playback
>      – USB Asynchronous Mode for Record
> 
> It sports something like 16bit/48kHz with 89dB SNR.  That is both with
> regard to attainable sound quality as well as USB bus behavior
> completely lacklustre.  I'd expect this kind of interface to be mostly
> soldered to mainboards directly where one would not expect to be able to
> change buses at all.
> 
> Or be part of some USB sound interface in the $10 price class.

Mine's in a Behringer UCA202 that was $19 when I got it many years ago.

> So the idea to take this into low-latency realms with a view on realtime
> effects seems a bit optimistic indeed.  Actually out of place.  Maybe
> this isn't actually the interface we are dealing with but just something
> hardwired to the motherboard and thus cropping up in the lsusb output?

Don't know about the original poster, but my built-in audio shows up on 
the PCI bus.

-- 
David W. Jones
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authenticity, honesty, community
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