Cubemap seams in Unity 5.3.4 on iOS

Unity Engine
1

I’m using Unity 5.3.4f1 and my cubemap’s have noticeable seams on iOS, but not in the editor.
My cubemap settings are: Lat-Long layout, bilinear filter mode, 2048 compressed.

In previous versions of Unity, these seams did not show up on iOS.

2

We have the same problem when the cubemap is compressed. When it’s not, the seam disappears.

3

I would love to not have them compressed, but this is for mobile and I will have about 10 - 2048 cube maps, so size is a major consideration. Compressed 12 MB each, Uncompressed 72 MB each!

4

In fact when they are compressed, the two side of the seam doesn’t match anymore, that’s why you see it.
(The same when you blur a cubemap, the two sides doesn’t match anymore).
If you compress it yourself with an external tool (like CubeMapGen from AMD), and provide it “as is” to Unity, do you still have the problem ?