I modify the TalkThrough_BF706Mini programme to implement an IIR filter. I debug the code and everything works perfectly with the subroutines provided by UweS ( https://ez.analog.com/thread/90496 ). But I have a problem with the RST button. When I pressed the RST button after I downloaded the programme to the ADSP-BF706 EZ-KIT, the filter was disabled and the sound from the speaker became the original sound(Without filtering). So I want to know what is the reason for this phenomenon?