Check the jack for broken solder joint, also clean the socket with the contact cleaner.

check sound card CD input header pinout
there's LGGR and LGRG the pin order variants
ground pins are soldered to one plane and you can see it on the back side of the PCB

Yep. I also vote it's the sound card's CD audio header pinout. Unless you have the original audio cable that came with a CD drive compatible with the SB Pro 2 (Panasonic interface), chances are your cable has the wrong pinout.

No big deal, just rearrange the pins on the header of the cable that goes into the sound card. You can pull out each wire individually by using a very sharp needle or hair pin to raise the plastic claw that holds the wire. Once raised, you should be able to pull out the wire and reinsert it into the correct spot. It's a clean operation without need for cutting or splicing wires. Just be careful not to get the needle into your finger 😅

Very interesting inputs. Thanks! I will go ahead and look at that CD header and reflow some solder. the CD cable I am using is a non SB Pro 2 original cable. So, if the reflow won't work then I'll look at the cable.

Well, it was a cold solder joint on the CD audio header. I flipped the card upside down and saw two potential cold solder joints, so I reflowed and it is good to go. Thank you so much!