My sprayer only makes a humming noise when I squeeze the trigger... anyone got anything on this?

It is probably clogged. Dis-assemble & clean or replace the spray head. The hose typically will not require replacement.

It could be plugged at the base of the sprayer with a large partical of sand or rust

I agree with Bones and Firefigherlong

Remove the sprayer head try if you have good flow the head is cloged, clean or replace,if no flow the hose may be clogged remove clean or replace, see the link below it might help, Thanks.

John
Kohler Plumbing (http://www.kohlerserviceparts.kohler.com/ServicePartsPage.aspx?DocumentID=9fe8d9f6ef4c446b9 f190ebdc990dfb8&ModelID=556ebdc2936d4f5d8d2dda4f02300621)

Here is a close up pic. Of a typical spray unit... disassemble unit, clean and reassemble.

If that doesn't work then the SPRAY DIVERTER VALVE itself may be clogged (see 2nd pic.). Depending on your faucet it should be easy to get to... usually under the spout, toward the back. Remove and clean... may need to replace entirely.

Let us know how you make out... ;)

MARK

You got good advice from Experts above. Just want to add:

If there is a lodged piece of dirt in the tip of aerator than water passing around that dirt makes the whistling / buzzing noise.