Lightmass Bleed

Hello all. Problem is exactly what it says on the tin. I have a room setup and light is bleeding through the seams on just about all my assets.

All lighting is static emissive, with a sphere outside of the room providing exterior lighting and a few rectangular, coloured lights inside. Light-map resolution is set universally to 1024. In this image, the bleeding can be seen at the bottom of the rectangular light and on the seam of the room:

I have read the official guide, and it offers no solution to light bleed save for when using dynamic lighting, which I am not. I have also looked at various other posts on the subject and found no solution.

Thanks in advance to any responses.

Just an update. I’ve modified the UVs to create more space between the shells. This has not solved anything. Close to giving up - nothing I am trying is working, and there are no solutions on the internet.