“Knot knot.”/“Who is there?”/“Earphones.”

Earphones tend to get tied into knots. An knock-knock joke is:
 
“Knot knot.”
“Who is there?”
“Earphones.”
 
The joke was posted on Twitter by Humourologist‏  on September 23, 2017.
 
“How to tie the strongest knot ever: 1) put some headphones in your pocket 2) wait one minute” is a related joke.
   
   
Twitter
Humourologist‏
@silver_starr_
Knot knot
Who is there?
Earphones
12:07 AM - 23 Sep 2017
 
Twitter
Read2smile‏
@Read2smile
Retweeted Humourologist (@silver_starr_):
Knot knot
Who is there?
Earphones
1:28 PM - 23 Sep 2017
 
Twitter
Pnkj 🇮🇳‏
@Arey_sharmaji
Replying to @beyhaddhh @rehan00344
Knot knot
Who’s there ??
Earphones 😟😟
3:59 AM - 5 Nov 2017
 
Twitter
jolly dad jokes‏
@dadtellsjokes
Knot knot
Who is there?
Earphones
7:15 PM - 29 Dec 2017