It's time to clean the Roland D-50 key contacts. Wash your hands
because you might touch the contacts.
We will use cotton swabs and
(rubbing) alcohol, at least a 91% solution, available at drug stores.
70% solutions because they don't evaporate as quickly, or cleanly, and can
over-wet the carbon contacts.
Even a 97%
solution might take a day or two to dry out before the contacts operate
Don't use a lot of alcohol. Just slightly moisten the swabs then
softly wipe the black, printed
circuit contacts (right).