“I have a Polish friend who is a sound engineer and I have a Czech one too”

Sound engineers often test by saying, “Check one-two.” A joke has been printed on several images:
 
“I have a Polish friend who is a roadie for a band. I have a Czech one too. A Czech one too. Czech one too.”
   
The joke was posted on Twitter by Ollie on June 27, 2016.
 
           
Twitter
Ollie
@ojedge
I have a Polish friend who is a roadie for a band.
I have a Czech one too. A Czech one too. Czech one too.
5:20 PM - 27 Jun 2016
   
Reddit—Jokes
I have a Polish friend who is roadie for a rock band
submitted June 29, 2016 by flekkie
I have a Czech one too. Czech one too. Czech one too.
 
1 July 2016, News Mail Bundaberg (Bundaberg, Queensland), pg. 17:
I have a Polish friend who is a roadie for a band. I have a Czech one too. A Czech one too. A Czech one too.
 
Reddit—Jokes
I have a Polish friend who does microphone tests for bands.
submitted July 9, 2016 by AStrayLamia
I have a Czech one two. Czech one two. Czech one two.
   
Reddit—Punny
I have a Polish friend who’s a sound engineer… (self.Punny)
submitted September 5, 2016 by ButtonKing
and I have a Czech one, too. Check 1, 2.
   
Reddit—Dad Jokes
I have a Polish friend who has a job as a sound engineer… (self.dadjokes)
submitted March 2, 2017 by madazzahatter
I have a Czech one too…
 
Reddit—Jokes
I have a Romanian friend who does tech for Broadway productions…
submitted March 6, 2017 by mewtucas
I have a Czech one, too!
 
Reddit—Oneliners
I have a Polish friend who is a sound engineer and I have a Czech one too.
submitted March 17, 2018 by wtfover
COMMENTS
Juanathan54
Could u explain I’m being stupid

ezquir3
Sound engineers say “check 1, 2” into a mic to see how it sounds. Czech replaces check but is also his friend’s nationality hence the play on words
 
Reddit—Oneliners
I have a Polish friend who is a sound engineer. I have a Czech one too.
submitted October 2, 2018 by MaxAMM0