This is a sound effect library I got. As you can hear, it’s muffled. Is there any good way I can fix this?
That’s two links. You need to be careful how you post.
The voice at the end sounds muffled because I think the original is a highly compressed sound file and somebody expanded it out to a WAV for shipping.
Once you compress sound, you get the compressor damage (honky, bubbling, muffled) and it never goes away. It doesn’t matter if you copy the work to a higher quality sound format. That just makes the damage a lot easier to hear.
You can use the Equalizer Effect to accentuate the high sounds…
…but the woman has pumping hiss noise behind her and the noise is going to get really loud if you do that. The blue line is a rubber band and you can push it around to get the effect you want.
Typically, you can’t recover from compression damage. The voice track doesn’t have any frequencies past 3KHz – like a telephone, so there’s nothing there to boost.