Un expected problems in the interferograms

Hi everyone,

I used the snap+stamps to perform a PS processing. I noticed there are some unexpected problem in several unwrapped interferograms. there are dense fringes somewhere. As far as I know, there is no apparent deformation in these areas. And other interferograms in the time seris are normal. the following image is plotted in stamps using (ps_plot(‘w’)).
image

Then I went back to check the inteferograms in the snap (see figure below). I noticed the phenomenon mentioned above already appeared during the processing in snap.
1537088309(1)

Does anyone know the exact reason and how to solve it? Thank you very much.

Luna