Problem with merging layers with color overlay effect set to blending mode other than 'Normal'

[Gavin3087296347wi]

So one of my layers has a Color Overlay effect(fx) and then i used 'soft light' on that very same Color Overlay effect. Now problem arise when i tried to merge the layers and the image it produce was not quite the same. I know we usually use the 'Snapshot' Merging techinque ( shift+ctrl+alt+E) to merge the layers but on this case it does not produce the same result. I think Photoshop just merged the Effects(fx) and produce this 'faulty' image. Can someone please help me with this problem. Will be super grateful. I am happy to  elaborate further if required. 

thank you.

[D Fosse]

View at 100% and try again. Is the underlying image a noisy or "binary" image (line art, halftone screen etc)?