Well, ok this will get a little complicated because there are a few issues at play here.
The first problem is the pants. Your events state that the pants animation will play from the beginning every single frame your character is moving. So your pants animation never leaves the first frame. The thing that I find works well for triggering animations is to make them actions to key presses and releases. So "on Key press D - play animation" for example.
The sound issue is the same as the pants. A new sound will play for every tick that you hold down the D button. That means that the sound is just piling up because you'll have hundreds of them playing all at once.
You could try removing everything from the audio event and just make it "Pants - Animation Frame = (whatever frame you want the sound to play) - play sound".
I hope that's clear enough.