Issues with downmixer example

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Apologies if I missed some answer to this question. My issue is with the ADF example in examples/advanced_examples/downmix_pipeline.

I'm currently using the master branch for ADF which I cloned with the --recursive tag, so I'm in particular using IDF v4.4.4 (git commit hash g3c8bc2213c), with python 3.9.

The last time I tried this demo was last year, and I had no problem at all. However, when running it with the aforementioned versions, I get a problem I cannot pin down. I'm using an amplifier to which I send raw i2s signals (I'm not using the internal DAC configuration) with some pin configuration (which is already sorted with a board.h file in my board component), and the audio in general is not a problem (I've run some examples to play a single file successfully and with behaviour as expected). However, the downmixer has now a rather strange behaviour:

When running it in bypass mode (with the line

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downmix_set_work_mode(downmixer, ESP_DOWNMIX_WORK_MODE_BYPASS)

) the output audio is glitchy, shattered, and not what is supposed to be. However, when the downmixer is turned on in order to run the second channel (

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downmix_set_work_mode(downmixer, ESP_DOWNMIX_WORK_MODE_SWITCH_ON)

) everything is suddenly fine: the audio is crystal clear as it is supposed to be. I'm very puzzled by this because, from the documentation, I understand that bypass mode does not change what it does to the base channel (it will still go through the resampling element and so on), so why would the output be so different? Why would bypassing downmixer degrade the quality of the signal? The problem must be in the downmix element, since when running the exact same audio file (from spiffs as well) in another example (e.g. player/pipeline_spiffs_mp3) everything runs as expected.

I've changed nothing from the example in the sdkconfig (a part from custom audio board), so I'm not sure how helpful would be sharing this. If there's any other data needed from my end please let me know.

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I put a little more detail in a github issue. For updates, here is the link: https://github.com/espressif/esp-adf/issues/1010