Hi All, I have a project running an ADAU1701 that does not want to work correctly. The ADAU runs on a 22.5MHz clock originating from a DIR9001. Fs is set at 44.1kHz with the program length on 1x (1024), both of the PLL's are pulled high for MCLK= fs x512. The I2S input works fine, and so are all the filters. However, the analog input and all of the GPIO inputs are not working correctly and can be seen jumping up and down with a level detector in sigma studio.
Strangely if I set the program length to 2x (512) analog input and GPIO's work fine, though the analog now has a noise-floor of -30dB. But filters are now messed up, a 2k -6db notch moves towards 3.5k for example. As far as I have understood from the ADAU datasheet, for a 44.1kHz sample rate the program length should be 1x (1024), is there a setting I am missing?
Schematic digital part:
Schematic analog part:
Registry settings in sigma studio:
Screencapture of Sigma Studio: