I am making a cross-platform recorder and for some functional requirements, I need to use the frequency detection of 18kHz, but I encountered a problem. My samplerate is 48kHz, which should theoretically receive up to 24kHz. My computer browser can reach the maximum of 24kHz normally, but my Android mobile browser became 8kHz and the maximum for the IOS mobile browser is 15kHz. I have searched for a lot of information but still have no idea. I have also changed many different codes to execute, but the wav files recorded on the mobile phone are only 8kHz~15kHz. Can you please tell me how to solve this issue?
I have tried many different recording codes and executed the recording function, but no matter which system's phone I use, the file captured is always between 8kHz to 15kHz.
Thanks in advance.
