AS3 - FastForwad / Rewind in Flash Video Frame does't change properly.

Here is My Code

private function StartForward(evt:MouseEvent)
        {
            trace("StartForward Called");
            SeekSpeedFor = SeekSpeedFor +10;
            trace("SeekSpeed: " + SeekSpeedFor);
            SeekPointFR = myVid.playheadTime;
            trace("Initial PlayHead Time: " + SeekPointFR);
            myVid.stop();
            RewindFlag = false
            ForwardFlag= true;
            myVid.addEventListener(Event.FRAME_CONSTRUCTED,OnConstructFrame);

        }


        public function OnConstructFrame(evt:Event):void
        {

            if(ForwardFlag)
            {
                if(myVid.playheadTime >= SeekPointFR)
                {
                    trace("Before Seek Cal.: " + SeekPointFR);
                    SeekPointFR = SeekPointFR + SeekSpeedFor;
                    trace("After Seek Cal.: " + SeekPointFR);
                    myVid.seek(SeekPointFR);
                    if(SeekPointFR > ftime)
                    {
                        ForwardFlag=false;
                        myVid.removeEventListener(Event.FRAME_CONSTRUCTED,OnExitFrame);
                    }
                }

            }



    }

I guess issue may be of buffer... i have set bufferTime to 30 sec.... for a 60 min video i get frame changed after 15-20 min video get played.. this is my guess.. plz help me out if anybody have idea.

show me the code.