He tinkered with the sound, making sure it was audible, yet would not interfere with conversation.
To date, however, Kim has only tinkered with the economic system.
He has merely tinkered with programs written by others.
Have you tinkered away for years in your garden shed creating the product which will change the world?
I tinkered in the garage until I found a way to attach Velcro type hook fasteners to a mop head so I could clean with terry cloth towels.