Removing Oxidation from Magnetic Switch Contacts

We have gold plated magnetic stainless steel switch contacts that are malfunctioning, and we presume this is due to oxidation.

We are presently cleaning the parts in a bath of deionized water in ultrasonic cleaning equipment, but there is still a problem. What would you recommend?
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Prepare a bath consisting of 5 parts DeoxIT® GOLD (100% solution) to 95 parts OMS (odorless mineral spirits) or acetone, INSTEAD OF the deionized water.

Place components in bath, and process as usual with ultrasonic cleaning method.

Allow parts to air dry for 10-15 minutes (or until dry), and insert in equipment directly thereafter.

NOTE: If DeoxIT® GOLD is used directly following manufacture of the components, plating the stainless steel with gold might become unnecessary, thereby reducing production costs significantly.

NOTE:
DeoxIT® GOLD (formerly ProGold)
DeoxIT® SHIELD (formerly PreservIT)
DeoxIT® FaderLube (formerly CaiLube MCL)
DeoxIT® Grease Type M260 & L260 Paste (formerly CaiLube Grease).