I have a mod called "modern siren pack" that replaces the police siren sounds with realistically loud sounds. You can hear the siren echoing from a far distance. I installed 3 mods, one is an airplane sound mod that replaces the sounds for planes, the same kind of mod for helicopters, and then an ambient sounds mod that replaces the sound of cars revving in the distance when you go afk. after installing all 3 of these at the same time i noticed the police sirens were really quiet but still replaced. they dont have any echo effect anymore and you can only hear it when youre close to the cop car. I reinstalled the siren mod and it didnt fix it. im thinking the ambient sounds mod might be the cause. I installed it in ONESHOT_AMBIENCE.rpf. I dont care about this mod and would be fine without it. Could i replace oneshot_ambience with vanilla files? How come reinstalling the siren mod didnt fix it?

You can replace any file at any given time with the vanilla package.

I usually recommend (especially with sound mods) to test them after the install before installing another one.

That saves you (like now) a lot of time & troubleshooting.