OP Zero, Audio record latency

[kolegs]

Hi,

 

I got a problem with orange pi zero and audio record latency.

What I try to do is to record the audio on orange pi zero, send data to my phone and play it here, but the delay is big(around ~1-1.5s) that's is quite a lot. I've tested it for a few days now and I am sure the delay is on the device. What is interesting sending audio the other way(phone->orange pi zero) has no delay at all(~0.1s).

First I tried to use Qt(5.9) and QAudioInput, now I switched to alsa libraries but no results.
I also tried to use command line to check this

arecord | aplay

but still I can hear the delay.

 

Is there any way to decrease the latency?
 

Thanks for help in advance.

[Igor]

First you probably need RT kernel ?

https://forum.armbian.com/index.php?/search/&q=realtime kernel

[kolegs]

I've compiled RT kernel, is there any way I can confirm that it works?

And how can I advantage from RT kernel?

That's the version:

3.4.113-rt143-sun8i

 

[Igor]

2 minutes ago, kolegs said:

I've compiled RT kernel, is there any way I can confirm that it works?

And how can I advantage from RT kernel?

Sorry, don't work with RT much and officially we don't provide RT kernel, so I moved this topic out from technical support area. Perhaps some other RT / audio expert could provide you more help on this topic.

[kolegs]

I was wondering if I need RT kernel anyway, since I don't need latency at the level of 10ms, I just want to make P2P connection and send audio data online to talk, so the latency at the level of 0.5s are acceptable. But I am not sure where can I look for an answer.

 

EDIT:

I tried to set buffer to smaller and it works. Need to port it to my software.

arecord -B 320 | aplay -B 320