When your Keurig makes noise when it's off it can be a result of the needles being clogged and needing cleaned which causes water pressure buildup even after being shut off.
The water is trying to purge and so is making the sounds.
You can press and hold the brew button with no K cup to help the water in the lines purge.
Make sure the Keurig doesn't have a pod in it and it's plugged into the wall and hold the brew button for 10 seconds and you should hear the pump going and watch for a small amount of water to come out.
To force your Keurig to reboot start by turning off the Keurig machine and unplug it.
Then remove the water reservoir and wait at least 10 minutes.
After removing the water reservoir and waiting 10 minutes, plug the Keurig back in and turn the Keurig back on.
Next wait for the Keurig to recognize that the water reservoir is not connected and then reattach the water reservoir.
Then wait for the add water indicator light to stop flashing and open and close the K cup compartment.
You can also reboot your Keurig by pressing and holding the 9 oz and 10 oz buttons at the same time for 3 seconds.
The strong button on the Keurig is to allow for you to brew a more stronger and more concentrated cup of coffee.
When you press the strong button on your Keurig brewer it adjusts the brewing process to use a higher coffee to water ratio.
The higher coffee to water ratio, results in a bolder taste and essentially makes the coffee stronger by using more coffee grounds for the same amount of water.
Pressing the strong button on the Keruig activates the setting that increases the coffee strength.
when the strong button is pressed on the Keurig it extends the brewing time slightly and allows for more extraction of flavor from the coffee grounds.
To use the strong button on your Keurig, you simply press the strong button on the Keurig before you select the brew size to make a stronger and bolder cup of coffee.
Strong coffee is made by using a lower coffee-to-water ratio (more grounds, less water) and refers to the concentration of the beverage rather than the roast level.
Espresso coffee drinks by definition, are a strong drink since it's brewed as a very concentrated form of coffee.