Needed to replace the control switch for our ceiling fan because the post of the knob broke off.

Old switch had 2 wires coming off it and new one has 3.

Now fan hums... never did before. What's up?

Am having trouble finding 2-wire control switches at big box stores and local hardware. Will I have to special order? Or is there a fix out there utilizing the 3-wire.

All help is greatly appreciated!

Old/new. 2-wire/3-wire. Does not really tell us much.

Standard single-pole fan controls are typically 2 wires with a ground. A three way would have three wires plus a ground.

What type was the old switch? Infinite control or 3-set speeds?
What is the new one?

Infinite variable speed fan controls can make the fan very noisy.
Is the fan definitely on high speed at the pull chain? This is a must.

What make/model is the fan? How many speeds does it have?

Ceiling fan pull chain replacement and repair - Ceiling Fans N More (http://www.ceiling-fans-n-more.com/ceiling-fan-pullchain-replacement-and-repair.php)