Quick update. I received a quote back from the Hohner Shop for tuning and reconditioning my HM-926 and HM-927. $100 dollars per instrument.
The quote said the leakage could not be stopped because it was general leakage from the “vileda” pads which are old and dried, and which are not longer stocked.
I called and spoke with a pleasant customer service representative who told me the service rate is $100 per hour. Normally they do not service out-of-warranty melodicas, particularly older ones, she said, but since I paid for shipping to get mine there, they said they would service them.
I asked to speak with the technician and he is suppose to call me on Monday. I have a few questions. I will keep you posted.
So I guess I will have to start thinking about doing my own maintenance.
This may also impact purchasing decisions for used melodicas.