I can't get line in working on my CT3900. Everything else i tried works, including mic in. I tested with multimeter that the line in connector is soldered properly so the problem is somewhere else. Here are some pictures of the card. I can't see anything wrong.

Sound Blaster DOS mixer settings were also correct. I even tried to swap CT3930 in place and it's line in worked right away.

Any ideas what i should try?