Alright, I've had all I can take getting these custom sounds to work...
I've followed damageppy's method to the letter about what, five times? And even with packrat it still doesn't work!
So I'm asking the entire community, if I did EVERYTHING else with the designs of my map series, could someone help me in getting the custom sounds to work?

I'm sorry, I know it sounds lame, but right now, I'm frustrated as crap with this.
I've met all the requirements and I can even get the sounds to preview inside hammer. But they refuse to play in the map even if I pack the files into the map using packrat.
So please, if anyone has the time to spare on helping me with this 8 level series (nine counting the boss battle)

I have had problems with custom sounds before too. You don't need to pack it with packrat to hear the sounds on your own computer. How are you getting the sounds? There may be something with the sound file that is keeping portal from being able to recognize it, whether or not hammer can. Try finding a different way of getting the sound files.

Goldenknighttim wrote:
I have had problems with custom sounds before too. You don't need to pack it with packrat to hear the sounds on your own computer. How are you getting the sounds? There may be something with the sound file that is keeping portal from being able to recognize it, whether or not hammer can. Try finding a different way of getting the sound files.

Well, I'm converting youtube videos to mp3...
and then using Audicity to change them to the proper format (44110 MH at 128 KH .wav).
After that I follow DaMaGeppy's tutorial to the letter and it isn't working >_<'
I may try downloading them with Youtube-to mp3 next.

Converting a youtube video to mp3 through an online website was what I did when it wouldn't work for me. What I did to solve this was I used another computer that had a mic driver that I could use to record the sound through the outbound audio with audacity. I doubt the problem is how you are packing the sound file. I would try experimenting with different ways to get the sound file you are after. I don't personally know enough about sound files to know what you should be looking for. My advise is just to guess and check.

You know that YouTube's license doesn't allow redistribution. If you have permission to use the music you should be able to get the file another way.

Okay, after combining both methods (Damageppy's and Packrat) I finally managed to get the sound clips to work. Now it's just a matter of collecting up the sounds.
I also need to make my own core model and record/edit the custom voice clips.