[LAU] ACPI, HW and Jack issues? "[solved]"

Jostein Chr. Andersen jostein at vait.se
Thu May 14 06:02:34 EDT 2009


I', really sorry about the noise, but think I did it right this time:

On Wednesday 13 May 2009 23.06.05 hollunder at gmx.at wrote:
...
>
> The question is if this is a calculated or real (measured) value.
> Consider measuring with jdelay.

I physically connected a patch cable between the 1010's channel 3 out an in 
and then in qjackctrl connected jack_delay's out to system playback_3 and 
system capture_3 to jack_delay's in. Now, the picture changed totally:

With latencies 2.9 according to qjackctl:
capture latency  = 64
playback_latency = 128
   262.197 frames      5.946 ms
   262.190 frames      5.945 ms
   262.190 frames      5.945 ms
   262.190 frames      5.945 ms
   262.191 frames      5.945 ms

and with latency 0.726 according to qjackctl:
capture latency  = 16                                     
playback_latency = 32
   117.187 frames      2.657 ms
   117.190 frames      2.657 ms
   117.191 frames      2.657 ms
   117.191 frames      2.657 ms
   117.191 frames      2.657 ms

But this just mean that latency because the soundcard is at the best 2.7 ms 
when sending sound from it's out to it's in and it is better when just 
recording, right? And apps that is jack only connected still have 0.4 ms 
latency?

Thanks for pointing me to jack_delay.

Jostein








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