artifacting with URP on iOS with Unity 2021.2.2

Hi all,

Hoping someone can help with this. I just upgraded our project to Unity 2021.2.2 using URP and I'm having some issues with artifacting on ios devices (no issues in the editor).

Here's a clip.

https://www.dropbox.com/s/csu19somj4a37oh/artifacting.mov?dl=0

I have a bit of a weird setup. The background and ground is a sprite but I have a ground plan that the 3d characters run around on. This plane has a shader that just renders the shadows that fall on it. Here is a copy of the shader.

https://www.dropbox.com/s/1yncd8qr6x5tdxs/ReceiveShadowsBill.shadergraph?dl=0

On the forward render for the pipeline I have some render objects that control how different elements, including the sprite background, are drawn.

https://www.dropbox.com/s/ohk1je5tkwmcqq5/Screen Shot 2021-11-17 at 9.25.04 pm.png?dl=0

I have narrowed down the artifacting to be something to do with the ground plane and the background and I've spent a day trying different shaders and render objects but I can't seem to find a solution.

Would appreciate any input.

Thanks

 

OK I don't think it has anything to do with the ground plane that renders the shadows because the problem still exists when I turn that off.

So this really just leaves the background sprite. Here's another screenshot.

https://www.dropbox.com/s/fsszo5hhwi4zog7/IMG_1594.PNG?dl=0

Here's the camera and sprite setup in the scene (no idea where camera control handles have gone in the scene view, but that's for another time).

https://www.dropbox.com/s/a3ifzgkubaq7cq3/Screen Shot 2021-11-18 at 10.32.38 am.png?dl=0

Thanks

 

I should also mention that this background sprite just uses the Sprite-Default material