The KitchenAid mixer is shaking profoundly when I use it, what's wrong?

If your KitchenAid mixer shakes violently while in use, it could be due to a variety of causes:

One common cause is an uneven countertop surface, as the mixer relies on a stable base to function properly. Even the slightest wobble in the counter can cause significant shaking.

Another possibility is an unbalanced bowl, which can be caused by a dented or warped bowl, as well as uneven dough distribution within it. These factors can cause the mixer to wobble while operating.

Loose internal components within the mixer base are a less likely, but still potential, cause. While this scenario is uncommon, it could cause excessive shaking during operation. If the shaking continues after you've checked for uneven countertops and unbalanced bowls, loose internal components may be the cause.

However, resolving this issue may necessitate professional assistance, especially if you are uncomfortable disassembling the mixer yourself.
If you have additional information or insights, don't hesitate to share in the comments.