^ UV checker view

Essentially theres a stretched texture seam bordering my UV seams. Its the only uv set, it has no history or anything, transforms frozen.. Im stuck. The mesh is wielded together, no stray faces or anything. Mesh was cleaned.

Is it because its triangulated? Painting on it in photoshop or mudbox always causes stretching textures (cause of the seam obviously).

Any help would be greatly appreciated. This place seems active so hopefully I can get an answer.