Cartridge-slot cleaning is one of my favourite adventures to embark on. This was the method I was using at the time, but I would not present paper towel as the ideal material now because it can leave fibres behind in the connector.

The old “clean the cartridge contacts with an eraser” trick is abrasive as well. It can shift stubborn contamination, but I would not treat it as routine maintenance. Start with the least aggressive cleaning method that works and, above all, don’t leave extra fluff or debris in the cartridge slot. That’s a big no-no! :D

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