I have tried a lot of fixes that have been mentioned on this forum as well as other places in on the web . nothing has worked so far . I would really apreciate it if some one can help me with this .
It looks like you have taken all the standard troubleshooting steps like resetting PRAM,SMC and volume
in sound/system preferences. The next best action I could suggest was to contact Apple.
Take it to the Apple store. Inconvenient but the problem can be resolved.