Maximum of phone 2 users are facing the same cracking issue on ear piece speaker output. Speaker output lacks proper optimization and also the phone lacks proper equilizer to tweak sound.
For temporary fix you can consider the below Wavelet preset after downloading the app form play store and set the buffer size as 2048. Limiter and Channel Balance should be left untouched as it is already perfect.
Hope nothing will look into this issue in future as it is hampering existing phone 2 users experience and also loosing potential buyers due to this issues.
