How to remove mosaic lines between images with gdal

Question

Maybe this is a simple issue but I couldn´t find a solution for it. I used gdal (gdal merge, and also trying with buildvrt and translate) for mosaic 8 sentinel 1 images in osgeo4w shell and it seems fine except when I zoom in and find white lines where the stitch was made, please see screenshots below:

enter image description here

enter image description here

Have been looking for possible solutions within gdal tools and its parameters, but so far nothing worked. Saw something mentioning a -cbind but not sure how to apply it, that is, if it is really useful in this case. If someone can help, I´d really apreciate it.

Thanks.