Best equipment to not listen to coworker's respiratory sounds?

I have a coworker that is next to my cubicle that clears his throat and makes other ‘snot’ sounds through sniffling, all day every day, 8 hours straight, as a chronic habit.

The room is very quiet otherwise; I tried some musician’s earplugs that I had but the snot sounds went right through them.

Should I try for those earmuffs they use at the shooting range, or are those designed more for loud noise suppression? I wonder if the snot sounds will go right through them.

Or is some kind of white noise the better option?

You don’t listen to music?

You could still try noise cancelling headphones, but they may not get the job done as well on the snotty sounds without music coming in. (Although they do work very well even if you’re not listening to sounds.)

Based on what Ive read, the noise cancelling works on louder, constant non human noise like airplane engines.

Garrote?

I have noise cancelling ear buds. They work!

I am able to block out the neighbor’s loud parties.

Maybe rig up a device that automatically makes a loud obnoxious sounds back at him every time he does his thing. Like a gun.

Tactful communication?

I just got these Bose noise cancelling headphones from a friend for xmas.

Listening to a podcast last night, I never heard my gf come home. Scared the crap out of me when she tapped me on the shoulder.

Oh, you’re no fun.

Regards,
Shodan

I have a similar problem at work so I got noise cancelling headphones and I listen to mellow music. It works for me, though I really prefer to hear what’s going on around me.
Can you move to a different cubicle? Work from home?
I have one co-worker in the room with me who when he sneezes I tend to say “Yuck” instead of “Bless You” and another co-worker in the next room (there’s no insulation in the walls) who thinks he’s an opera singer. Or has conferences calls with the volume at 11. Those headphones saved my sanity.