i2s_read with ICS-43434 always reads zeros

[captain_morgan]

I've been at this on and off for a frustratingly long time. I can get various I2S input examples to work but when I start working on my own code with a relatively new IDF I cannot get anything but zeros from i2s_read.

Most examples use i2s_read_bytes
I seemingly cannot find an example that uses an external I2S device *and* uses i2s_read instead of i2s_read_bytes. This means I don't really have a test case to work against. But I can at least verify the hardware I'm working with is functioning and my pinouts are correct with the code below.

I'm using this board.
https://www.tindie.com/products/microwa ... ple-alexa/

This code works when compiled with Arduino 1.8.9 and Arduino ESP32 1.0.2
https://github.com/maspetsberger/esp32- ... erDemo.ino

With the Serial Logger I can clap my hands, shout obscenities, etc and clearly see it working.

Why won't my code work with i2s_read?
I've got a whittled down my code to this test case https://gitlab.com/morganrallen/i2s-test-case
Compiling against IDF 691b81ec2 there are no issues. It runs as expected but simply reads zeros.
When really reduced, the only major difference is the i2s_read call. Is this broken? Am I overlooking something? Any input would be helpful, I'm at a loss.

[captain_morgan]

Welp, I'm still at a loss as to why this will not work outside ESP32 Arduino 1.0.2 so I've filed a bug.

https://github.com/espressif/esp-idf/issues/4015