Ultra++ external microphone jack works fine for a minute then it stops getting sound

Hello, first of all, I’m thankful that I finally found a soundcard which does what I need.

Though there is one problem currently:

I’m building a musical instrument running puredata on raspberry pi to process audio in real-time. So basically the audio from a pickup comes in through the microphone jack, gets processed in puredata and is played at the same time through the headphone and speakers. The first minute everything is fine, but then after that the sound on one side of the headphone and speaker gets killed and after about 30 sec it stops completely making any sound. After restarting the signal processor of pure data it works fine but again only for about one minute. I don’t have this problem when I use a usb soundcard, so it shouldn’t depend on the software.

I’m thinking maybe it’s a problem of performance. Is the soundcard suitable for real-time processing at all? And maybe if I deactivate the speaker which I don’t need anyway, it would get better, what do you think? (and how could I deactivate it?)

The other thing is that the chip on raspberry pi gets really hot usually because of the processing. And since the soundcard is directly on top of it, maybe the heat causes this problem? but that would not make sense because after restarting the software it works again immediately.

[UPDATE]: I actually found out that the problem isn’t with the speakers or headphone jack. It’s the external microphone jack that stops working after a short time. I found this out accidentally when some recorded loop was still playing but no sound was getting in through the mic jack.

I’d be glad if we find a solution

Thanks in advance!

Hi and welcome Sallar

If I had to guess I think this could be coming from something changing the alsa setting (puredata?) after one minute, to investigate an idea of what you could try:

When the sound is working as you want, in a terminal save your Alasa configuration:

sudo alsactl --file working_configuration store

When this is not working anymore save it again on a different file:

sudo alsactl --file not_working_configuration store

Then try to restore the working configuration:

sudo alsactl --file working_configuration restore

is it working again?
With a text editor try to see if you have any difference between working_configuration and not_working_configuration