uaudio - distorted output

[Alexander Leidinger]

Quoting Hans Petter Selasky <hps at selasky.org> (from Sun, 8 Oct 2017  
13:19:19 +0200):

> On 10/08/17 12:56, Alexander Leidinger wrote:
>>
>> Hi,
>>
>> attached are the config descriptors and the device dump of two  
>> uaudio devices. Both exhibit distorted audio output. It sounds a  
>> little bit like clipping / not feeding enough samples fast enough...
>>
>> I played around with dev.pcm.2.bitperfect=1,  
>> dev.pcm.2.play.vchans=0, dev.pcm.2.play.vchanrate and  
>> hw.snd.latency=1...10.
>>
>> At some point vchanrate doesn't work anymore, it always stays at  
>> 4.0 audio, even when trying to go back to 2.0. I have to usbconfig  
>> reset the device.
>>
>> Sometimes (rarely) when playing around I get clear audio output,  
>> but when I try to reproduce it (going back to default value for the  
>> last sysctl setting and then going back again to the same setting  
>> again), the audio is distorted again.
>>
>> To me it sounds like some kind of buffer is not big enough or the  
>> data is not delivered fast enough to the uaudio device. But this is  
>> a dual-socket system with:
>>     CPU: Intel(R) Xeon(R) CPU           E5620  @ 2.40GHz  
>> (2133.36-MHz K8-class CPU)
>>     FreeBSD/SMP: Multiprocessor System Detected: 16 CPUs
>>     FreeBSD/SMP: 2 package(s) x 4 core(s) x 2 hardware threads
>> And while playing around with uaudio the system has a load of  
>> around 1, so I would expect CPU/RAM is not an issue here.
>
> Hi,
>
> What version of FreeBSD is this?

current as of r323636

> Try to enable hw.usb.uaudio.debug=16 during playback.

No such sysctl, only hw.usb.debug....
I did the hw.usb.debug=16, but no output in dmesg nor  
/var/log/console.log nor /var/log/messages, where do I need to look?

Bye,
Alexander.

-- 
http://www.Leidinger.net Alexander at Leidinger.net: PGP 0x8F31830F9F2772BF
http://www.FreeBSD.org    netchild at FreeBSD.org  : PGP 0x8F31830F9F2772BF
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