Sound stuck on my Mac

sorry if this thread already exist but i don't had the time to find it out and i'm not in the mood.

I got a seriously problem with my sound on my Macbook Pro.
When i open a software (Traktor Dj Studio, or Ableton Live 7) what i use to play and make music my sound 'stuck' and sounds very ugly.

I already reboot my mac and installed everything all over again and i hope everything will be fine again but its not.

I still have the same problem.
All my software is original i installed everything clearly and i tried with 2 different soundcards (Ozone interface and Audio 8 ) but still sound stuck

Is it a hardware problem or software i dont know what to do to fix it.

sorry my english is not so great who can help me out of it ?

thank you so much

the volume is good everything works, but when i play something with this programs (traktor or ableton) the sound stuck and sounds crispy like a streaming that is not buffered enough or a damaged speaker.

and also by ableton my CPU stands on '4' when nothing is going on, maby it is a problem with the cpu options.

Only with music software it does this strange thing. Because everything else works perfect.

I was surfing on internet and somebody say

you must Turn off Airport

and seriously my sound on my mac doesnt stuck anymore

but it is still strange why my sound stuck when my Airport is on and when i turn it off my sound doesnt stuck

what can help to fix this problem now?

I want to produce music with my Airport on
because now i have to put it off

i want to do both of them

is there anyone who can help me??