212- That made me chuckle. Was visualizing that!!
There's a few things that I could mention, however, the humiliation would kill me.
However, remember my student days putting on my headphones, calling the tower, then wondering why ther're not hearing me! Radio was on, squelch set ok, right freq, speaking loudly into headphones, nope there working, what the hell!!
Shut down, then realised I had plugged headset into the wrong jacks, it was in one of the passenger jacks!

Problem corrected, pleasant flight had....