The easiest way, I know of, is to to just under 100% using the sliding scale in the lower left corner and then go to the Audio menu and increase the volume. A c

The easiest way, I know of, is to to just under 100% using the sliding scale in the lower left corner and then go to the Audio menu and increase the volume. A click on Increase Volume goes up to the nearest number divisible by 5 (i.e. at 97%, clicking Increase Volume goes to 100%; at 92%, you need to do it twice).