On my '17 Pro 4X I recently noticed a click sound under the following conditions: engine on (or off with ignition on), gear selector in park. The click occurs when I press and when I release the brake pedal. The noise appears to come from inside the center console near the gear selector. I suspect it's the solenoid that locks the gear selector in park unless the brake is pressed. The issue is I've only recently noticed the click (I've had the truck for 2 years), and I'm wondering if this recent revelation might be an omen of something getting ready to fail, or have I just recently started paying more attention to the sounds my truck makes?