How can I delete .wav metadata without changing any of its features?

Question

I have to delete additional info from .wav header so it can be processed by another program. After some search I have tried to use ffmpeg, for example:

ffmpeg -y -i $filename -map_metadata -1 -codec copy $filename

or

ffmpeg -y -i $filename -map_metadata -1 -c:v copy -c:a copy $filename

However, while the new .wav file maintains old features, both of them cut the length of my .wav files that are longer than 4 seconds, for example 4,9 seconds becomes 4,03 in some cases, and the recorded voice is cut.

What can I use for my purpose? I need new file with same features (16bit, 16000Hz, mono, 256kb/s) but without info.

Answer 1

FFmpeg does not edit file in place. Output has to be different.

ffmpeg -y -i $filename -map_metadata -1 -codec copy $newfilename