I was recording a friend playing piano. My setup was an electric piano (like a clavinova) line out to line in on a windows laptop. I tried recording a few seconds and it sounded fine but I let him record through the rest of it and at the end listened back. It came out like this https://soundcloud.com/rwjhughes/bad-audacity-record . I thought maybe if I exported it would fix it because it is not exactly a high spec computer but it came out the exact same.
I tried a few effects and played with the settings and either got no change or they removed the clicks but degraded audio quality. I have good experience with audacity and similar software but couldn’t crack this one. We could record it again with better settings or a proper audio interface if we can get one but it would be easier if there is some way of getting by without.
It’s mono and set to receive the low-level, delicate signal from a microphone, not the robust, powerful stereo signal from a keyboard. Every time you stress a note or chord, it crackles, right? That’s the microphone amplifier overloading.
I am aware of laptops with line in and mic, and yes I just used the mic and it was overloading at the start (not sounding like the one on the audio file given). I turned the piano down very low and the kind of crackling sound became unnoticeable on a test record, it was only near at the end of the session when i listened back and heard skips, that sounded different to the over amplification noise.