Online just suggest micro-fiber cloth & can of compressed air.
I don't need to do that because I just want to clean the keys themselves and when I play the keys have a slight tacky feel to them.
I think it's the coating on the keys that absorbes moisture and turns them tacky. They press & raise back up fine after keys pressed..it's just the 'feel'.
Is there a way to place something on it to absorb the moisture?