Hello Thomas

at first it is recomended to initialise your struct like this:
i2s_stream_cfg_t i2s_cfg = I2S_STREAM_CFG_DEFAULT();

and then override the default values

like in the samples

if you do not have an i2s to dac then you need to define
SOC_I2S_SUPPORTS_ADC_DAC

you can also try this ...

Hello ThomasESP32

at first it is recommended to initialise your config with
i2s_stream_cfg_t i2s_cfg = I2S_STREAM_CFG_DEFAULT();
and then override the default config values

If you have no i2s to DAC chip you have to use the internal one

for this you have to define
SOC_I2S_SUPPORTS_ADC_DAC ...

I am trying to initialize wifi in an function and call it in the main.c

I am using esp-idf v4.4.3 and esp-adf v2.4.1
I wont use the wifi for an audio stream its just for an webserver to change some settings

you can see the initialization code here
its the same like the wifi get started example ...