Delay in playing(recording?) real time raw audio in LINUX

Question

I'm developing OpenWrt device which sends audio data to network but I have issues in the early beginning.

I'm trying to find which cause delay in playing (or maybe recording, but more probably playing) real time record from microphone.

For example I run arecord | aplay on my Debian machine and the delay in playing is somewhere between 500-1000 ms.

When I run the same command on my OpenWrt box (TP LINK wr703n) I get almost the same delay (Same to cat /dev/dsp > /dev/dsp)

When I stream sound using netcat(with UDP) from OpenWrt box to Debian PC (on LAN) I get almost the same delay. I think It does not depend on sound card - on OpenWrt I use usb sound card connected via hub and on Debian machine I use integrated notebook sound card.

Which could cause this delay? Or do you know possible solutions?

Thank you and sorry my english :)

Answer 1

I did the same thing, the reason for it, would be couple things, the processing power on the 703n, and if you do it wirelessly you will notice it too, I would look into wireless configuration and switch from 20 hertz band to 40, and change the encryption to tkip+aes, you should get 150mbps data rate instead of 60 or so that should help reduce the delay.