discuss-gnuradio
[Top][All Lists]
Advanced

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: Audio sink aU underrun


From: Jeff Long
Subject: Re: Audio sink aU underrun
Date: Sat, 28 Jan 2023 06:36:19 -0500

Have you tried a sample rate of 48000? If the audio sink is not accepting the specified rate of 32000, and is expecting samples at 48000, then there would be underruns. The high processor utilization for pulseaudio says something is going wrong there. Maybe it's spending all its time logging errors.

On Thu, Jan 26, 2023 at 11:17 PM Rakesh M <rakeshm2504@gmail.com> wrote:
Dear All,

I am having a Zynq based custom hardware which  runs GNU radio.

My platform is an old one
GNU radio version 3.7.4
linux kernel 3.17.0
Custom platform is AD9361+Zynq combination. Similar to AD9361+Zc706 with an audio codec.

I am trying to access Audio sink block to play back an audio. When I connect a signal source to the Audio sink .I get "aU" underruns consistently. When I connect it to other widgets I am able to see spectrum, time domain waveform etc.

When I try to monitor system activity I observe that CPU cycles are consumed by Pulse Audio application when unit spits out "aU". "htop" print attached. As I understand pulse audio stands between GNU radio and ALSA.

Query :: How to have an audio link without the burden of Pulse Audio application??
My aim is to avoid audio underruns.

My aim here is to run some signal processing on FPGA (FM demodulation - we have system generator tool sets for this purpose) and finally use GNU radio Source block to relay audio output from FPGA  to an audio sink ie GNU Radio Source block will generate audio data and not IQ samples. Preferable audio sampling rate is 48kHz

reply via email to

[Prev in Thread] Current Thread [Next in Thread]