Lowering player sounds makes it quieter, but i would like to disable the sound without lowering other sounds

You could open the jar file with 7zip (or any zip program) to go into the resources and replace the sound file with a silent one. Though it would be nice to have it in the mod itself, this would help for now.

Alternatively, you can create a resource pack consisting of a path to the file where the silent/other file should be placed.