im not real sure about the s-boats sensor ability so perhaps its something with the s-boat having a hydrophone issue, but then it shouldn't just be certain ships??????????
since you like the s-boats you might want to try my s-boat mod? its about making them more realistic which also makes them fragile but its great white knuckle fun
also, when you uninstalled the game, did you manually open your drive and delete any remaining ubi files in it? often corrupted files are left behind, especially if you uninstall the game while mods are still installed so if you uninstall the game while mods are still installed you definitely left files behind that instantly recorrupt the new installation