I have just built a board with ADAU1701 dsp. If I program it to feed generated square wave to the outputs, I get it on my speakers. But when I'm using it to manipulate input signal I get no sound on the output. While debugging, I accidentaly shorted one of ADC inputs with ADC_RES pin, and found out that when they are shorted, sound appears at the output (though very noisy). What could be the problem resulting in such thing? I'm using default resistor values for inputs.