...

Leveling a component on compliant footers:

To level an audio component on compliant footers, start with one footer near each corner. If the component weight is fairly evenly distributed, the component will be level and no adjustments necessary. If uneven, leveling is easily accomplished.

...

A component that is heavier on one side might compress compliant footers more on one side than the other. In such a case, move the footers on the light side of the component incrementally towards the heavier side until the component is level, as illustrated here:

Leveling a component diagram

...

You might have to move a footer farther back on one side than the other, or move one or more laterally (left to right) at the front or back.

...

Because the bottom plate is often thin gauge, it's usually best to keep the footers near the edges where the component chassis is most strong and rigid. This is usually most appropriately accomplished using four footers instead of three.