On Tue, 2022-03-22 at 10:45 -0300, Bruno Rohde wrote:
Turn OFF (or ON) the "use callbacks" checkbox in the audio dialog.
That did the trick, with callbacks ON DSP works. I never used it before, and to be honest, I don't know what this does, but for now it solved the problem. Could you (or someone) explain briefly what this is for? Is there any impact elsewhere (maybe performance) by using it enabled?
From what I understand, using callbacks means that Pd processes audio as soon as it is provided by JACK. This means, Pd doesn't add additional latency as JACK client. But it also means, that when Pd isn't quick enought with writing back processed data, the whole JACK process with all clients experiences a drop-out.
Without callbacks, Pd is less tightly coupled to JACK and uses a ringbuffer for input and output. The size of the ringbuffer is set in the 'delay(ms)' setting in the audio settings. From my experience, setting it too low causes Pd to not process audio at all. In my experience, this value is below 5ms, but this probably depends on JACK's blocksize setting.
Roman