i've managed to solve the crackling sound. it's the way the emulator code was written.

i never realized this problem until now because i've been doing testing with the phone connected via USB: when i unplug the phone from the USB, the sound becomes super choppy and it struggles to keep up. it's like the emulator is slowing down?? when it's plugged into the charger, sound is almost smooth (98%).

if i unplug the charger and run the emulator, i can replicate the *almost smooth* sound playback by pressing on a key. i don't need to be focused in the emulator's window to replicate this. i can press and hold a key in the desktop and the sound playback will be smooth.

hmmmmmmm