Hello,
its a real basic question which I have.
I do not get any audio output.
In an tutorial I have seen that someone marked the checkbox "compute audio" in the main window of PD (first picture) to solve this poblem.
But I do not have this checkbox (second picture). There is only the phrase "Audio aus" (which is German for "Audio off"). But I can not click anything around that phrase. The DSP checkbox I can check and uncheck, but without any audio changes and the phrase "Audio aus" is not changing.
I'm using Pd version 0.52.1.
What can be the problem?

@nenleh said:

In an tutorial I have seen that someone marked the checkbox "compute audio" in the main window of PD (first picture) to solve this poblem.
But I do not have this checkbox (second picture).

Ancient tutorial, then. The current "DSP" checkbox is the same as the old "compute audio" box.

What can be the problem?

The console messages that you get after clicking DSP say that it's an audio driver problem: Pd is trying to connect to an Advanced Linux Sound Architecture instance and this is failing.

Linux audio is famously messy. The current best attempt to clean up the mess is Pipewire, so I guess your best option may be to install Pipewire and run pd under its power. If it's me, I'd use the Media menu to choose the JACK backend and then run pd as "pw-jack /path/to/pd-gui" (I think; not at the computer right now, and the path may vary depending on Linux distro).

I have not yet used Pipewire, though, so I couldn't troubleshoot beyond that. Linux audio forums could help more. (Note that Linux audio being chaotic and disorganized isn't Pd's fault -- but once you get the audio subsystem configured, then it works for every app. It's painful only the first time.)

Also, "priority 6 scheduling failed" means that you should add your user to the "audio" group.

hjh

Before attempting to install anything, like pipewire (I'm a Linux user and have never used it, TBH, it's the first time I read about this, didn't know it before), go to Media->Audio Settings, and try to choose another input and output device. It may be that the device Pd chooses by default is not working. It might also be that you get two devices with the same name. That's the case with my laptop, where I have two "HD-Audio Generic" entries (actually four, two tagged as "hardware" and another two tagged as "plugin"), but the first ("hardware" tagged) doesn't work, while the second (again "hardware" tagged) works fine.

Thanks to both of you.
The solution from alexandros worked - the sound now is working. And yes, its another output with the same name which was chosen by default.
I had not considered it as an solution because its realy the same name.

Here the screenshot (in case someone in the future with the same problem finds this):

You can add this to your startup flags by going to File -> Preferences -> Edit Preferences, and choose the "Startup" tab. At the bottom of this window, in the "Startup flags:" entry, type "-audiodev 2" (at least this is what I had to type), and then relaunch Pd to see if it chooses the right device on startup. If it doesn't, experiment with the number, which should be the same as the position your device has in the list of your screenshot (I thought this was 1-based, but it appears to be 0-based, so the first item in the list is 0).
Even with this flag by default, if you want to launch Pd from the terminal with another device at startup, you can still do it, as the command line flag will override the one you have set in Pd's Preferences.