Hi Martin.
I could not find any part that could be pushed by the front panel. But I noted that, once the amplifier is on, there is a slight vibration that can be felt when touching any metallic part that is connected to electric ground. It looks just like if there was an issue with the insulation between secondary and primary parts (I suppose this vibration is 50Hz). I removed the front panel and I checked again that programming was possible by directly touching any pin. Then I did the same while touching with my other hand a metallic part of the device: the programming was no more possible until I stop touching the metallic part. So I wonder whether I found the nature of the problem – even though I still have to find the source of the problem. On the other hand, maybe this has nothing to do with the sensitive keyboard issue because it seems to me that I already felt this kind of faint vibration on the metallic part of the front panel at the time when the amplifier was working nominally.
Any idea about this vibration when the amplifier is on? Thanks.
Robert