I picked up this instrument used, and it was listed as "some buttons stick." Exactly as I expected, as soon as I picked it up I heard the tell-tale rattle of bits of decayed rubber grommet linkage shifting around in the box. Opened it up and it's all crusty dried-out rubber, and I've got two different diameters of silicone tubing coming in the mail to try out on it.   I got a partial refund from the seller because the item in its case arrived with some smell of mildew. I'm not seeing a