What am i doing wrong? exec("lame --decode $newfile $wav_name_new"); unlink($newfile); exec("sox -t wav $wav_name_new -t wav -s -w -c 2 - trim $start $duration | sox -t wav -s -w -c 2 - -t wav $wav_name fade h 1 $duration 2"); exec("/usr/local/bin/faac -w -o $your_name_mp4 $wav_name"); exec("lame $wav_name $your_name_mp3"); unlink($wav_name); unlink($wav_name_new); PHP: