Not something I can help with, without seeing it. I deal with the mechanics without even knowing the notes, and wouldn't have a clue without an instrument in front of me. I guess just a self-employed tech, "not being a bassoonist", and certainly uncomfortable with messing with a bassoon ACOUSTICALLY, without specific instructions from an expert. I think most techs would be in the same position.
If your local tech cannot quickly find a mechanical fault, how about sending it to Chip Owen, associated with Fox. He's old and wise re anything bassoon, and a fantastic guy. I think he still actively does repairs.
If your local tech cannot quickly find a mechanical fault, how about sending it to Chip Owen, associated with Fox. He's old and wise re anything bassoon, and a fantastic guy. I think he still actively does repairs.