Had another posting about this where I had the error "file not found" in the MRL log when giving commands to MRL. I assume this was a timing problem, the audrey file was not ready at the time the playback started.

There is also the fact that raspi 2 by default has no MPEG 2 licence. You can buy it in the raspi shop for 2 pounds, so only a small fee. Unforturnately this however did not solve my sound problems.

Converted then all audrey files to MPEG 1 format using WinFF. This helped to make all audrey files audible using mpg123.

During my OpenCV session with Alessandro I asked him whether he could help me with this issue too. He tried to play a .wav file and a .mp3 files through the audio service of MRL. Both files gave no sound through MRL but worked with mpg123.

I have a Daffodil sound stick for speakers and microphone. I have modified my alsa-base.conf file to have the snd-usb-audio at index 0 and the snd_bcm2835 at index 1.
The micophone works (I can see the in the MRL log the confirmations for the words I say) but playing the file does not throw an error - just does no sound output.



7 years 9 months ago


thanks, thought I had the arduinos updated but just did it once again. On the first try I did not get connection but when I startet to change the port and pressed refresh a few times  it then connected

Also noticed that version 1.0.119 does not really shut down but hangs in the command window. Closing the command window and restarting mrl worked however for me.

Just so you know.. its not exactly "hanging" 

You are being effected by some new "features"  .. the feature is called the Agent service which is responsible for starting, stopping, and managing different instances and versions of MRL ..

Sorry for the confusion and I'm glad you found a workaround ...


7 years 8 months ago

Thread has got some serial connection issues added but to come back to the initial problem:

Raspi can use the USB microphone but with MRL (Alessandro talked of a java issue) for the speakers we have to use the Raspi audio jack and not the USB one.

Make sure in the Raspi Main Window right upper corner to set the speaker default to analog (unfortunately can't post a picture here)



7 years 8 months ago


Check the .asoundrc file in your home directory


ls -al

pg .asoundrc 

It may override the default settings.




7 years 8 months ago

Hi Mats

thanks for pointing me to this .asoundrc file. it tells me 

pi@raspberrypi ~ $ pg .asoundrc
pcm.!default {
type hw
card 1
ctl.!default {
type hw
card 1
and aplay -l shows
(EOF):pi@raspberrypi ~ $ aplay -l
**** Liste der Hardware-Geräte (PLAYBACK) ****
Karte 0: Set [C-Media USB Headphone Set], Gerät 0: USB Audio [USB Audio]
  Sub-Geräte: 1/1
  Sub-Gerät #0: subdevice #0
Karte 1: ALSA [bcm2835 ALSA], Gerät 0: bcm2835 ALSA [bcm2835 ALSA]
  Sub-Geräte: 8/8 ...
So from what I interprete is that .asoundrc should point to card 0 instead of card 1?
however - why is the USB microphone working in my environment and what is pcm. and ctl. meant for?