Problem with forward view zoom

Any help with the following problem would be much appreciated:I have been using FS2004 for a year now and have always had my view forward zoom set to 0.87 in the panel.cfg for every panel I have used. I have not experienced a problem until the last few days.When I start to accelerate down the runway my screen suddenly jumps and my cockpit zoom returns to 1.00.Thank you in anticipation.Kindest regardsAlan