After dragging footage to media pool, NOISE added

I have some footages recorded from my phone and they do not have noise.
But, after dragging these footages to the media pool of DaVinci Resolve 15, the footages have NOISE,
especially when the audio level reaching to red.
What should I do to handle this problem? Please advise.

Many Thanks
Ivan

Check the audio sample rate and codec.

By noise do you mean in the picture or audio? If audio and the signal is in the red a lot you are probably hearing distortion. The only way to stop this is to record with a lower audio level keeping the signal out of the red.