Well I just bought a dq sound and I went on youtube to get this thing i want for my dq sound i downloaded the video went to windows movie maker and cut out the parts I dont need. I did that and I tried uploading it to my dq sound and it said not packed in Riff container. http://www.youtube.com/watch?v=C0-lbKTanxo It's starts at 1:45 and ends at 1:48.
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Sooo how can I upload that part for my dq sound?

Ok, here's what you can do.
Go here: http://www.youtube-mp3.org/
And put in the youtube address and then download thr mp3 of the sound. Now you have just the sound from the youtube video.
Next, google Audacity and download it for free and install it. The import your sound clip to audacity. Cut out the sound you want and move it to the beginning. Delete all the excess. Now you should have a sound clip that you want. Export it as an Mp3. I don't remember if Audacity can export .wav files, but if it can't, go here. (From this tutorial. Give it a read too.)
Convert your Mp3 to a .wav file and upload it to your Custom Dq. Click the little play button and make sure you can hear it. Then just to be safe you can do an ingame test too. If all works, then you're sweet.
That should all work. It was a while since I did mine.

Okay well I downloaded audacity I opened it opened the part I cut out from windows movie maker earlier exported it to wav uploaded it to my dq it said that I uploaded it successfully I pressed the play button and it played the previous owners sound. Then I put the whole video on audicity and tried to cut out parts but it wouldn't work. So can you try?

So you did everything right but then it played the previous owner's sound. Delete your custom folder, go ingame /dl yourself and test and see what sound it is.

I just did that and it didnt work. On forums it still says the old owners sound and ingame it doesn't say anything. I'm so frustrated right now.
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Got it. Thank you (Echoforce and Solax)