I resoldered mine with a decent iron and yeah it’s quite difficult because of the component size and proximity to other components. Even with a decent setup I made a bit of a mess. I’m used to welding too haha. If you’re able to do it you can save $50+ on a new control board. If you’re not comfortable the price for a new control board can be worth it. That said, it’s worth a shot. What are you going to lose if you mess it up with a cheap iron? If you get it right you get a functioning OP1. If you mess it up you have to fork out, which is what you’d have to do anyway.

If the above doesn’t work try wriggling the jack in the socket to see if the contact has come loose from the control board. If it has come loose, you may need to re-solder the audio output component’s contact(s).