It actually was because of the mixed nature of the problem, but yes, it was a complete

. I disconnected everything the first time it failed, but the keys were still not working. Then, I decided to plug and unplug the membrane and everything seemed to work but I reconnected the expansions and I found that the G was failing again. So, I thought "hum, this is the classic crap that happens when the membrane starts to fail". In summary, since the numbers were failing as well from time to time I thought that all the problems had a common source. However, after covering the tracks with more silver, I found that everything was working very well until I connected the expansions and the G stopped again. This already made me think that there could be another additional problem

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Good news is that at least the connectors are very clean now and the membrane has a nice additional layer of silver on the tracks. Hopefully, it will last a lot of time like that (fingers crossed) although I am ordering a couple of spare membranes, just in case. I also discovered that tooth paste works wonders as superfine sand in these situations. You almost do not remove any of the silver, but it is possible to see that the paper, towel or whatever you are using becomes a bit gray. It probably removes just a few microns

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