Today, I normally checked the MP after a flight. Touching the engines, in one I perceived a slightly higher temperature than the other three which had the same temperature. I thought that something generated friction and so by hand, I tried to turn the engine casing comparing it with the others. When doing this operation, turning the box, you notice a "roughness" when it rotates. In doing so, I noticed that the engines have different "roughness". In fact, front left and rear right, show a "harder roughness", while the front right and rear left have a "softer roughness. Does it happen to you that an engine heats up more? Do you also have this difference in motors mounted in the diagonal axes?