Re: [Discuss-gnuradio] GRC uses OSS instead of ALSA??

[Tom Rondeau]

On Mon, Jun 2, 2014 at 12:54 PM, John Meloche <address@hidden> wrote:

Hi guys,

 

My application requires that I use a multi-channel audio device as an audio source.  I have in my system of hardware the Presonus 1818VSL external USB device.  This audio source is definetely working correctly with Ubuntu as I can monitor the level of each channel using Ardour without any preconfiguration whatsoever.

 

My problem is that I am having absolutely no luck in trying to establish a connection between GRC and my multi-channel sound device (Presonus 1818).  I have uninstalled pulse audio and made the chages to the /etc/modprobe.d/alsa-base.conf file  as per these directions.  I know for fact that this did work about two months ago, at that time, I was measuring each audio input in GRC using a scope sink.  It was beautiful and it worked fantasticly) http://forums.presonus.com/posts/list/28993.page

 

Regardless of how my multi-channel audio source is delcared (i.e. blank, hw:0,0 or plughw:0,0)  GRC will always report that the OSS source has no file or directory.  I have read that OSS was discontinued quite some time ago.  How can I force GRC to use only the ALSA audio source?

 

I have attached a couple of screen shots showing my very simple flowgraph and the ALSA mixer info.

 

Thanks in advance for any advise to get me rolling in the right direction.

 

John

John,

Any chance you've reinstalled anything in the meantime since this was working before? We haven't (iirc) changed anything in the gr-audio system recently. Generally, this is a dependency problem. The gr-audio was reworked a few years ago, but it's now less verbose about telling you what audio subsystems are and are not being built and installed. Take a look that libasound2-dev is installed (the's the Debian/Ubuntu name for the package). If you don't have the alsa dev package installed, it won't be built. So if that's the case, install the dev package, then rerun cmake and rebuild GNU Radio to try and recover it.

Tom